SPECIAL MORPHOLOGY: MOSSES. 



181 



disproportionally thickened, that the horizontal partitions formed, 

 by the drying of the cells, project laterally, as well as towards the 

 interior and exterior, and are then designated trabecula. The inner 

 lobules, when they are connected together as a membrane, are 

 always merely the remains of torn cells. 



I have here given the history of the development of the archegonium 

 from confessedly proportionably circumscribed and incomplete observa- 

 tions of my own. By way of illustrating the terms applied to the indi- 

 vidual parts of the ripe capsule, I here give the analysis of the sporocarp 

 of Hypnum abietinum (fig. 134.) My investigations, combined with what 



l.H 



has here and there been contributed by others *, may perhaps suffice to 

 confirm the representation given. It is very evident that there are still 

 great deficiences to be lamented, and that innumerable questions present 

 themselves, especially as to the manner in which separate cells and 

 masses of tissues have originated. What appears from the facts with 

 which we are already acquainted is, that so far as the history of the 

 formation is known to us, a rending of a continuous mass of cellular 

 tissue, but nowhere a blending together of divided parts, is apparent, and 

 consequently that it is as yet, scientifically speaking, incorrect to regard 

 the Moss capsule as grown together from different pieces. The very 

 simple structure of the archegonium makes it certainly in the highest de- 

 gree improbable that it will ever be found to be grown together out of 

 different parts. The second point to be observed here is,that the arche- 

 gonium consists of continuous cellular tissue from within outward, and 

 consequently that the development into layers of different cells need not 



* Especially H. Mohl, on the Spores of the Cryptogamia, Flora, 1838, vol. i. p. 33. ; 

 History of Development of the Capsule and Spore of (Edipodium Griffithianum, &c., 

 by W. Valentine, Ann. of Nat. Hist., Aug. 1839, p. 456, &c. 



134 Hypnum abietinum. A, The upper part of the seta (a), with the theca (6), the peri- 

 stoma (c), and the operculum (d). B is a part of the inner peristoma, with pro- 

 cesses (), and cilia (ft). 



N 3 



