MuscALES.] BRYACE^E. C)5 



this, and adds to the hst of porous Urnmosses, Octoblepharum cyUnch-icum, Didvnio- 

 don spliagnoides, and Leucobryum minus, albidum, and longifoliunV 



Mr. Griffith (Calc. Joum. v.) strenuously advocates the sexuaHty of the Antheridia 

 and Pistilhdia, regarding the former as a true male apparatus, and the latter as a pistil 

 contaming an o\'nle. I do not know that he has anywhere adduced proof of the validity 

 of this opmion ; and it is difficult to comprehend upon what e\ddence that theory 

 depends ; it may, however, be presumed, that he considers the spores to be analogous to 

 embryos, fonned in vast numbers. This admh-able observer thinks, that cA-idence in 

 favour of fecundation in some way in Mosses and Liverworts, is afforded by the 

 breaking up of the tissue, terminatmg and closing what he calls the style, that is to say, 

 the point of the pistilhdium, subsequently to the apphcation of a particular matter, 

 whereby the style becomes a canal, openmg externally by a browning observable in 

 the orifice of this canal, extending downwards until it reaches the cavity of the (his) 

 ovary, and by a corresponding enlargement of a cell (his ovule) existmg in that 

 ca\ity. jVIr. Valentine, however, does not regard these appearances as coimected with 

 fecundation. 



An miinitiated person, reading the definition of a genus of Urnmosses, might sup- 

 pose that to be the tribe in which an approach to the animal creation most nearly 

 takes place. Unacquainted with the exact meaning of the Latin words employed by 

 Bryologists, he might understand by the peristomium a jaw, l^y the calyptra a nightcap, 

 and by the struma a kind of goitre ; and when he saw that teeth belonged to this jaw, 

 he would natm'ally conclude that it was really a vegeto-animal of which he was reading. 

 Struck with the evident absm'dity of gi\Tng such names to parts of plants, without at the 

 same time explaining their real nature, I formerly ventured to call the attention of 

 naturahsts to the subject by the following paragraph in the Outlines of the First Prin- 

 ciples of Botany. 



" The cah-ptra may be understood to be a convolute leaf ; the operculum another ; 

 the peristomium one or more whorls of minute flat leaves ; and the theca itself to be the 

 excavated distended apex of the stalk, the cellular substance of which sepai'ates in the 

 form of spomles." 



The reasoning upon which I conceived this hypothesis to be sustained, was the 

 following : — Every one agrees in describing the calyptra as a membrane arising from 

 between the leaves and the base of the yoimg spore-case, and as enveloping the latter, 

 but having no organic connexion with it : when the stalk of the spore-case lengthens, no 

 coiTesponding extension of the parts of the calyptx'a takes place ; so that it must be 

 either ruptured at its apex (as in Jungennannia), or at the base ; and m the latter case 

 it wovdd necessarily be carried up upon the tip of the spore-case, which it originally 

 enveloped. Now, what can be more reasonable than that such an organ, situated as 

 thus described, should be one of the last convolute leaves of the axis which the spore- 

 case terminates, bearing the same relation to the latter as the convolute bractea to the 

 flower of Magnoha, or, to speak more precisely still, as the calypti'iform bractese to the 

 flower of Pileanthus I If the calyptra be anatomically examined, especially in such 

 genera as Tortula and Dicranum, no difference in its tissue and that of the leaves will 

 be observable ; and that veiy common tendency to dehisce on one side only as the 

 diameter of the theca increases, which characterises the dimidiate cal^-ptra, may be 

 understood to be a separation at the line where the margins of the supposed leaf united ; 

 in the mitriform calyptra this separation at a given hue does not take place, and the 

 consequence is an irregvdar laceration of its base. The analogy of the calyptra being of 

 this nature, the next inference would naturally be, that the part it contains corresponds 

 with a flower-bud. Upon this supposition, the external series of parts belonging to this 

 supposed bud would be the operculum ; the adhesion of tliis organ to the spore-case, 

 which would answer to the apex of the axis, or to the tube of the calyx of flowering 

 plants, would be analogous to what occurs ui Eucalyptus, or perhaps more exactly to 

 that of Eschscholtzia. As to the number of the parts, in a state of cohesion, of which 

 it is made up, it will be observed that in the paragraph above quoted, it is stated to be 

 one only. My reason for adopting this conclusion was the absence of any trace of 

 division upon its surface or in the substance of its tissue, and also the apparent identity 

 of nature between it and the calyptra when both are young, in the Tortula and Dicra- 

 num genera already cited. With regard to the peristomium : — The teeth, as they are 

 called, occupy one or more whorls ; they are evidently not mere lacerations of a mem- 

 brane, because they are in a constant and regular number in each genus, and that 

 number is universally some multiple of 4, as the floi-al leaves of flowering plants are 

 ordinarily of 3, 4, or 5 ; they have the pow er of contracting an adhesion with each other 

 by then* contiguous margins, as the floral leaves of flowering plants ; they alter their 

 position from being inflexed with their pomts to the axis, to being recurved with their 

 points turned outwards, — exactly as happens in flowering plants ; the teeth of the inner 



