Fertilization in Collema. 
759 
gynes, which is seen in the manner in which the latter converge about 
a group of spermatia. In growing towards a spermatium and often coiling 
about it the trichogyne shows a greater activity than that which has been 
described for other Lichens. 
4 - The spermatium fuses with the trichogyne to which it has become 
attached. After this fusion the cross-walls of the cells next to the long 
terminal cell exhibit the characteristic changes which have been described 
by other investigators.' 
5 . It is very evident that the spermatia and trichogyne are functional, 
and that there is not merely a reduced form of fertilization in Collema 
pulposum . 
6. In the number of male cells and the manner in which they are borne 
Collema pulposum forms an interesting link between the red Algae and such 
Ascomycetes as Pyronema and the Mildews. In its reproductive structures 
there are many points of resemblance to such representatives of the Laboul- 
beniaceae as Zodiomyccs and Rhynchophoromyccs . 
Madison, Wise., 
February , 1912. 
Literature cited. 
1. Acharius, Erik. : Methodus qua omnes detectos lichenes secundum organa carpomorpha ad 
genera, species et varietates redigere atque observationibus illustrare. Stockholm, 
F. D. D. Ulrich., 1803. 
2 . : Lichen ographia universalis. Gottingae, Just. Frid. Danckwerts, 1810. 
3 . : Synopsis Methodica Lichenum. Lundae, Svanborg et Sos., 1814. 
4. Baur, Erwin : Zur Frage nach der Sexualitat der Collemaceen. Ber. d. deutsch. Bot. Ges., 
vol. xvi, 1898, pp. 363-7. 
5 . : Die Anlage und Entwickelung einiger Flechtenapothecien. Flora, vol. lxxxviii, 
1901, pp. 319-32. 
6. : Untersuchungen liber die Entwickelungsgeschichte der Flechtenapothecien, I. 
Bot. Ztg., vol. Ixii, 1904, pp. 21-44. 
7. Bornet and Thuret : F^condation des Floridees. Ann. d. Sci. Nat., Bot., vol. vii, ser. 5, 
1 867, pp. 137-66. 
8. Cornu, M. : Reproduction des Ascomycetes. Ann. d. Sci. Nat., Bot., vol. iii, ser. 6, 1876, 
PP- 53 - 112 * 
9 . Crombie, J. M. : A Monograph of Lichens found in Britain. 1894. 
10 . Darbishire, O. V. : Uber die Apothecienentwickelung der Flechte Physcia pulverulenta , 
(Schreb.) Nyl. Jahrb. f. wiss. Bot., vol. xxxiv, 1900, pp. 329-45. 
11 . de Bary, A. : Comparative Morphology and Biology of the Fungi, Mycetozoa, and Bacteria. 
1887. 
12 . Dillenius, J. J. : Historia muscorum. 1741. 
13 . Fink, Bruce: The Lichens of Minnesota. Contrib. from U. S. Nat. Herb., vol. xiv, 19TO, 
pp. 1-269. 
14 . Flotow : Lichenologische Beitrage zur Flora Europaea. Bot. Ztg., vol. viii, 1850, pp. 553-9. 
15 . Fries, Elias Magnus : Lichenographia Europaea reformata. Lundae, Typis Berlingianis, 1831. 
16 . Funfstuck, M. : Beitrage zur Entwickelungsgeschichte der Lichenen. Jahrb. d. Kgl. bot. 
Gartens zu Berlin, vol. iii, 1884. 
