The Origin and Development of the Apothecium etc. 403 
only serve as a means of retaining the spermatia, but may also serve 
as a protection against drying. The trichogyne in my material differs 
front that described for all other lichens in the greater length of its 
terminal cell and in the direction in which it grows. It never protrudes 
from the surface of the thallus but grows more or less parallel to the 
plane of the thallus toward some place where spermatia are produced. 
Sturgis (76) does not describe in detail the development of the apo- 
theeium in C. pulposum. However, he says of Leptogium myochroum, 
“the points observed by me have beeil entirely comfirmatory of the 
results obtained by Stahl from his study of this species and of L. 
microscopicum . . . The same remarks apply to C. pulposum (Bernh.) 
Nyl. and C. nigrescens (Huds.) Ach.”. He figures only a yonng carp- 
ogone of C. pulposum. The young carpogones in my material before the 
terminal cell elongates are exactly like his figure. 
Spermogonia and Spermatia. 
While spermogonia have been described in a great many lichens 
by Tulasne, Lindsay, Glück and others, in some species they seem 
to be entirely wanting. Fünfstück concludcd that the genera Peltigera 
and Peltidea have no spermogonia, and Baur finds none in Solorina. 
ln all cases where they have been found they are pocket-like depressions 
in the surface of the thallus and contain innumerable cells, the spermatia, 
which are borne on specialized branehes, the spermatiophores, and which 
escape through the ostiole of the spermogonium. Spermogonia have 
been found very commonly in the Collemas. Nylander in describing 
the genus writes: “Spermogonia vulgo arthrosterigmatibus praedita, in 
paucis modo speciebus sterigmatibus simplicibus.” Lindsay also makes 
no exceptions of any species but says: “The spermogones of the genus 
are always immersed in the tissue of the thallus and more or less incon- 
spicuous. The spermatia are in all cases short, rod-shaped, and with 
obtuse ends. The sterigmata in all specimens examined by me are arti- 
culated, — sometimes ramose, — about 1/500 to 1/600 long, composed 
of short, roundish, or cubical cells.” Of C. pulposum he writes: “The 
edge of the thallus as well as the exciple of the apothccia are sometimes 
studded over with very conspicuous ragged, deep perforations which are 
the ostioles of old spermogones.” In var. tenax Hepp. (Sub. C. multi- 
florum) he found the spermogones “scattered upon the edges of the lobes. 
The envelop is of a deepish-brown cellular tissue. The spermatia are 
in myriads, rod-shaped, almost atomic as to size”. 
Stahl found both sterile and fruiting thalli in the form of C. pul- 
21 * 
