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fruitstalk. In a strictly natural arrangement, the species of this section should not be separated from Gymnostomum.
16. Phascum crispum Hedwig (curly-leaved Earth-Moss); stems densely tufted, short, subdivided; branches fastigiate ; leaves crowded, lanceolate-subulate, channelled, much crisped when dry; strongly nerved, margin involute; perichætial leaves very long, concave below; capsule roundish, rostellate, immersed, very shortly pedicellate. (TAB. V.)
P. crispum Hedw. St. Cr. i. t. 9. Sp. Musc. Turner,
Musc. Hib. Smith, Fl. Brit. Eng. Bot. t. 1680.
and Taylor. Bryol. Eur, fasc. 1. p. 13. t. 6.
Astomum crispum Bryol. Eur. fasc. 43. tab. 1. Hab. Banks and fields, chiefly in calcareous soil.
Fr. Spring Stems usually much crowded, cæspitose, 2–6 lines in height. Stemleaves crowded, erect or spreading, sometimes reflexed, acute, margin involute, nerve strong and excurrent; perichætial leaves much longer, wider and concave at the base, linear-lanceolate, erect, or sometimes turned to one side, all of them much crisped and incurved when dry, yellowish-green, of close texture, areolæ opaque, except near the base, where they are larger and diaphanous." Capsule on a very short pedicel, immersed in the perichætial leaves, roundish, pale brown, the beak or persistent lid oblique, shorter than the capsule, Calyptra dimidiate, yellowish. Spores smaller than in most of the allied species, ferruginous-brown, roughish. Barren flowers terminal on the branches of the fertile stem (sometimes in the axils of the upper leaves, according to Bruch and Schimper), gemmiform; antheridia with few or no paraphyses.
In this moss, the lid, though perhaps not spontaneously dehiscent, separates very readily from the fully ripe capsule, yielding to the slightest lateral pressure. The mouth of the capsule, on removing the lid, is exceedingly small, about five times the diameter of the spore.
Specimens, gathered in Northamptonshire by the Rev. M. J. Berkeley, have
the capsules occasionally exserted on a longer pedicel ; but this character varies on the same individual. In this state it is P. rostellatum of Hooker and Taylor, and differs from Bridel's moss, so called, in the much larger perichætial leaves, the stronger nerve, involute margins of the stem-leaves, and in the shape of the capsule.
Weissia aciculata and W. longifolia Mitten MSS., found in Sussex, appear to be varieties of this species.
17. Phascum multicapsulare Smith (tall crisp-leaved EarthMoss); stems elongated, loosely tufted ; leaves distant, widely spreading, crisped when dry, lanceolate, apiculate, margin plane ; capsule roundish, immersed, rostellate. (TAB. XXXVII.
P. multicapsulare Smith, Fl. Brit. Eng. Bot. t. 618.
Astomum multicapsulare Bryol. Eur. fasc. 43. Suppl. t. 3. var. B. Mittenü; stems rigid, fragile ; leaves shorter, rigid, acute, recurved, scarcely crisped when dry; perichætial leaves smaller ; capsule on a longer pedicel ; spores larger. Astomum Mittenii Bryol. Eur. Suppl. fasc. 43. t. 2.
Hymenostomum sphæricarpon Mitten, in lit. Hab. In fields, rare ; in cart-ruts in Clapham Park Wood, near
Clapham Fordend, and in other places near Bedford, March, 1799: Rev. Dr. C. Abbot. Wet fields, near Darlington, Yorkshire, Mr. Backhouse. Appleton, Cheshire, W. Wilson. var. B. at Hurst Pierpoint, Sussex, on wet clay banks by a roadside, March, 1846; rare : Mr. Mitten. Fr. March.
Stems į inch long or more, sparingly branched. Leaves distant, dull green, shorter and broader than in the preceding species, rather obtuse, apiculate, the margin plane, very minutely crenulate, nerve excurrent, thinner and less defined, areolæ larger and less opaque ; perichætial leaves twice or thrice as long as the rest, erect and incurved, all of them less crisped when dry than in the preceding ; hence the stems, in the dry specimens, are remarkably slender. Capsules almost sessile, roundish, sometimes 2 together on the same receptacle, rostellate, the beak or persistent lid about half as long as the capsule, oblique. Spores and calyptra as in P. crispum. Barren flowers terminal at the extremity of a branch, often clustered, gemmiform; antheridia mixed with paraphyses. In var. ß. Ở A. usually lateral, as shown in Bryol. Eur., but sometimes terminal and clustered, as in var. a.
This is distinguished from the preceding by the wider, plane, apiculate leaves, less crisped when dry. The specimens sent to Weber and Mohr (Bot. Tasch. p. 477.), from Mr. Turner's Herbarium, belong to P. patens, with serrulate leaves ; that species, as also P. cuspidatum, having been sent by Dr. Abbot to Mr. Turner, named by mistake P. multicapsulare. The description in Fl. Brit. “ foliis nunquam exsiccatione crispis,” is inaccurate : in Eng. Botany, the leaves are correctly stated to have “some tendency to curl, though not in the same manner as P. crispum, and the points often incurved or contorted when dry.” Our specimens agree with an original one given by Mr. Sowerby to Mr. Borrer.
Our var. B Mittenii may perhaps be a distinct species, and is so regarded by the authors of the Bryologia Europea; but we find the position of the barren flower too variable in this and the allied species to be relied on as an essential character; and there is also good reason to believe that, in the same place where this variety was gathered in 1846, the ordinary form of P. multicapsulare only was found in the following year; hence it would appear that P. Mittenii is only an accidental variety.
P. polycarpon of Br. and Schimper is said to differ from our moss in the large, ovate-lanceolate, entire leaves, not crisped when dry, and in the curved elongated pedicel. It may possibly be a tall state of P. carniolicum.
18. Phascum rostellatum Bridel (beaked Earth-Moss); stems short, tufted, simple or branched ; leaves linear-lanceolate, spreading, crisped when dry, margin plane; capsule ovate or elliptical, rostellate, scarcely exserted. (Tab. XXXVIII.)
P. rostellatum Bridel, Bryol. Univ. i. 46. Nees and Hornsch. 1. c. t. 6. f. 14. Schwaegr. Suppl. t. 296.
Br. and Schimper, Bryol. Eur. fasc. 1. p. 13. t. 6. Hymenostomum obliquum Wilson in Eng. Bot. Suppl. t.
2831. H. phascoides Schimp. and Wils. MSS. Bryol. Eur.
fasc. 42. t. 1.
Astomum rostellatum Bryol. Eur. fasc. 43. t. 1. Hab. On the dried beds of shallow pools. Mere, Cheshire, W.
Wilson. Newcastle Town Moor, Mr. Robinson and Mr. John Thornhill. Sussex, Mr. Mitten. Fr. Autumn, Spring.
Stems 1–3 lines in length, simple or branched, cæspitose. Leaves spreading, entire, crisped when dry, lower ones lanceolate, upper ones linear-lanceolate, obtuse, nerve excurrent as a short mucro, margin plane, colour dull green. Capsule elliptical, olive-brown, on a pedicel little more than its own length, and generally overtopped by the perichætial leaves, rostellate, the beak or persistent lid about half as long as the capsule, oblique. Spores and inflorescence as in the last.
Å smaller moss than P. multicapsulare, with a smaller elliptical capsule, and longer pedicel. It so nearly resembles Hymenostomum squarrosum, that the two may possibly be only varieties of one species. This resemblance has already been noticed in Bryologia Europea. P. rostellatum, however, has shorter pedicels; and in our specimens the stems are more branched, and the perichạtial leaves are longer. The form and texture of the leaves are exactly the same in both.
It is remarkable that Bridel and others assert that Phascum rostellatum was first discovered in Britain ; but we have seen no authentic specimen of earlier date than 1832; and even that is referred to a different genus, in Bryol. Eur.
SUBORDER II. WEISSIEÆ. The Weissiez are allied on the one hand to Trichostomeæ, and on the other to Dicraneæ.
5. GYMNOSTOMUM. Beardless Moss. GYMNOSTOMUM Hedwig, Schwaegr. &c.
HYMENOSTOMUM R. Brown, Bruch and Schimper, &c. Capsule erect, on a straight fruitstalk, oblong, oval, ovate, or roundish, smooth, in a few species (Hymenostomum, partly), much contracted at the mouth, symmetrical, or sometimes a little oblique and curved. Peristome none; but, in some of the species of Hymenostomum, the top of the sporangium remains attached to the apex of the columella, thus forming a closed sac at the period of maturity. Annulus persistent and obscure in most of the species. Lid with an inclined beak, varying in length, conical at the base. Calyptra cucullate, beaked, extending below the operculum. Spores small. Vaginula oblong.
Perennial, growing on rocks, or on the soil; cæspitose ;
branched in a dichotomous or fastigiate manner; dwarfish, or elongated. Leaves lanceolate, or linear-lanceolate, spreading, when dry crisped, or erect and nearly straight, nerved, margin inflexed, plane or recurved, entire, areolæ small, dense. Inflorescence dioicous, or monoicous. Flowers terminal at first ; barren flowers gemmiform ; in the monoicous species ultimately placed near the base of the perichætium. Anthers and archegonin with paraphyses.
Closely allied to Weissia, differing only in the absence of a peristome. Name from youvoç, naked, and otwua, mouth.
After very close examination of the subject, we consider it right to discard the genus Hymenostomum, for the following
It is only where the capsule is very much contracted at the mouth, that the character, derived from the union of the sporangium with the apex of the columella, is apparent at the time of the dehiscence of the lid : in two of the species described in the Bryologia Europea (H. tortile and H. crispatum), it is not to be found at that period, and the structure of the parts is altogether the same in every species of Gymnostomum, if compared while the fruit is in an unripe state; even in ripe specimens of Gymnostomum xanthocarpum Hook. (which is closely allied to G. curvirostrum), the sporangium remains in union with the apex of the columella. Hence we infer that the character on which Hymenostomum rests is merely accidental, depending either upon the toughness of the membrane of the sporangium, or upon the less degree in which the columella contracts when drying. In the typical species of Hymenostomum, the aperture of the capsule is very much contracted by a thickening of the wall at that part, the inner layers of cells forming a horizontal ring, so that the orifice, bounded by a circle of 16 cellules, is barely sufficient to give egress to the spores. It will not be objected that this reunion of the two genera is opposed by the fact that their inflorescence and place of growth are different, so long as the genus Weissia is constructed with similar latitude.
Mr. Valentine has published some very interesting remarks on Hymenostomum in the Muscologia Nottinghamiensis (1833), and in Lin. Trans. vol. 17. p. 471., giving a more accurate view of the structure than had previously appeared: in the former work, however, the true diaphragm is confounded with the horizontal ring which surrounds the real aperture of the capsule ; due care not having been taken to distinguish or to define the terms “stoma ” and “ aperture.” If the term “aperture" be confined, as it ought to be, to the space surrounded by what is called the “marginal portion of the diaphragm," it is closed by the apex of the columella in conjunction with the membrane of the sporangium ; but if that term (aperture) be applied to the entire space covered by the operculum, it ceuses to be intelligible, and the so-called diaphragm, instead of being a single membrane, is composed of two distinct membranes, of which only the external annular one comes under the designation of “peristome" in the generic character given by Mr. Valentine, a name which is quite inapplicable if we include Gymnostomum tortile in the same genus.
The ring itself is analogous to what, in numerous mosses, forms the cellular inflexed base of the true peristome.
Sect. I. Inflorescence dioicous ; leaves scarcely crisped when dry, the margin
reflexed or plune, never incurved. a. Stems short ; perichætial leaves sheathing; capsule eliptic-oblong, narrow
at the mouth, lid conical, annulus large. Gymnoweissia. 1. Gymnostomum tenue Schrad. (slender Beardless Moss); stems cæspitose ; leaves lingulate, obtuse, those of the perichætium sheathing in the lower half; capsule oblong; lid shortly conical. (TAB. VII.)
G. tenue Schrad. Coll. Plant. Crypt. No. 31. Hedw. Sp.
37. t. 4. Web. and Mohr. Tasch. p. 86. Nees and Hornsch. Br. Germ. i. 151. t. 10. f. 14. Brid. Br. Univ. Hook and Tayl. Bruch and Schimp. Br. Europ. Monogr. p. 5. t. 2. Weissia tenuis C. Müller,
ing to specimens, without lid, in Herb. Turner.) Hab. On sandstone rocks and walls, not common. Cheshire. Near Glasgow, Mr. Lyon.
Fr. July, August. Stems very short, growing in broad light-green patches. Leaves suberect and a little recurved, when dry more erect, lingulate, obtuse, the upper ones the longest and more lanceolate, flattish, entire, or the marginal cells somewhat prominent and granulose, the nerve ceasing below the apex. Perichætial leaves larger than the rest, ovatelanceolate, convolute. Pedicel about 3 lines in length, pale yellowish, twisted to the right hand when dry. Capsule pale reddish-brown, the mouth reddish, a little contracted, somewhat furrowed when old and empty. Annulus persistent.
G. bicolor of Bruch and Schimper is allied to this, and differs in the acute, lanceolate, more spreading and recurved leaves. It is also exceedingly like Weissia reflexa Bridel, in every thing but the total absence of a peristome. G. calcareum Nees and Hornsch, differs from G. tenue in the rostrate lid, and belongs to the next section of the genus (compare Bryum paucifolium Dicks and Smith, above cited, which is said to have a rostrate lid). It is unknown to us as a British species. b. Stems taller, much branched; perichætial leaves slightly sheathing;
capsule ovate or oval, truncated; lid with a long beak; annulus narrow, persistent.
2. Gymnostomum rupestre Schwaegr. (rock Beardless Moss); stems densely tufted, slender, elongated, dichotomously