ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 171 



and critical remarks on species new to science or to the region. Ghroo- 

 ^occus limneticus Lemmermann is common in two ponds, among other 

 algse. The cells are 8-13 jx diam., and tend to divide much less in one 

 direction than in tke other two. The result is a 3Ierismopedium-\ike 

 thallus in surface view, but with an irregular outline, not square as in 

 Merismopedium. A new species, IficrocJuete naushonensis, is described, 

 growing on leaves of Sphagnum and other water-plants. Bulhochsete 

 Furberse, a new species, is most nearly allied to B. Brehissonii, but has 

 smaller dimensions, more celled audrosporangia, and more curved dwarf 

 males. B. elatior Pringsh. is here recorded for America. MiJcrosyphar 

 Porphyrse Kuckuck is fairly common in the fronds of Porphyra umbili- 

 calis. Nostoc punctiforme was found throughout the summer, so closely 

 associated with Sphagnum that it may be called symbiotic, occurring 

 sometimes on the surface of the leaves, but more usually inside the dead 

 •or empty cells. A new Erythrotrichia, E. rhizoidea, is described and 

 •critically discussed. E. S. G. 



Abnormal Conjugation in Spirogyra. — J. G. Bkown {BoL Gaz., 

 1918, 66, 2G9-71, 3 figs.). A short account of material of Spirogyra 

 nitida collected in the Rillito River, north of Tucson, Arizona, in April, 

 1917. The cells were conjugating in such a manner as to give the 

 appearance of a knot, one cell having connexions with three others, two 

 with two others, and the fourth with one other. Three of the conjuga- 

 tion-branches formed a triple connexion, and two other cases of triple 

 connexion were found on the same slide. Another lilament showed oue 

 cell monopolizing the energies of two cells in an adjacent filament, while 

 the neighbouring cell on each side had resorted to parthenogenesis. The 

 author attributes these abnormalities to such external factors as the 

 volume, temperature, and salt-content of the water. In the river in 

 question these factors are extremely variable, and the material here 

 described was collected in a pool which had undergone violent changes 

 due to floods of snow-water from the mountains, followed by evaporation 

 and consequent increase of salt-content. E. S. G. 



Cross-conjug'ation in Spirogyra Weberi. — Beet Cunningham (5o^. 

 Gaz., 1918, 66, 272-3, 1 fig.). The author records the occurrence 

 of cross-conjugation in Spirogyra Weberi, in addition to that described 

 by him as occurring in S. inflata (1. c, 1917, 486-500). He compares 

 the length and width of the "two species, and gives figures of both. 



E. S. G. 



Germination of the Spores of Floridese. — Harald Kylin (Arkivf. 

 Botanik, 1917, 14, No. 22, 25 figs.). A detailed account of the germina- 

 tion of spores in each of the three types of Floridese germlings, as defined 

 by the author — (1) the germ-tube type ; (2) the attachment-disc type ; 

 (3) the upright type. In the first, the spore on germination forms a 

 tube, which is separated by a cell-wall from the spore, which remains 

 undivided. This type occurs in Nemalionales and in several Crypto- 

 nemiese. In the second type, the spore divides, without increase of 

 size, by a cell-wall vertical to the substratum, and the two cells proceed 



