' ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 49 f 



Family 3. Calotricliofe Thr. (Kivulariaceae Ebh.). 



Genus 1. Calotlirix Ag. 



Genus 2, Coleospermum Kocli. 

 Family 4. Scytonemacefe. 



Genus 1. Scytonema Ag. 



Genus 2. Mastigocladus Cohn (Stigonemese). 



The forms included in the genus BJiodococcus are distinguished 

 from the analogous forms in the genera Chroococcus and Pleurococcus 

 by their purple, violet, or brown-red pigment. Many of the forms 

 included under Chroococcus arise from the breaking-up of filaments of 

 Cyanophyceas : — as C. minor from various species of Lynghya, C. 

 cohcerens from L. calcicola, C. membraninus from L. elegans, &c. In 

 the same way several species of Gloeocajysa are formed by the breaking- 

 up of sj)ecies oi Stigonema ; ihnd SynecJiococcus from Calotlirix salina. 



The author regards most of Kiitzing's species of Leptoth'ix and 

 Bosc's species of Oscillaria as the hormogonia of higher Cyano- 

 phycea3, such as Scytonemeaa, Calotricheae, and Stigonemese, pro- 

 pagating repeatedly by frequent divisions. These may become 

 invested in a more or less thick gelatinous sheath. Many so-called 

 species of Lynghya are only the young stages of development of those 

 species of Calotlirix and Scytonema to which they are found attached. 

 Although the blue-green algfe, as far as at present known, multiply 

 only non-sexually, they yet display in this a great pleomorphism. 



A large number of other genetic connections arc also traced by 

 the author. 



Class III. Ph^ophyce^. 

 Order I. Syngeneticfe. 



Family 1. Chromophytonese. 

 Genus 1. Chromophyton Wor. 

 Genus 2. Synura Ehrb. 

 Family 2, Hydrurete. 



Genus 1. Hydrurus Ag. 



New Freshwater Desmids.* — Mr. F. WoUe describes thirteen new 

 species of Desmids from the United States. 



New Diatoms from the " SaugscMefer " of Dubravica.t— Mr. F. 

 Kitton briefly describes the diatomaceous deposit {SaugscMefer) of 

 Dubravica, and gives a list of the new species and varieties, with 

 figures of three of the most remarkable — Epitliemia cistula, Stauro- 

 sira Harrisonii var. ampliitetras, and Surirella dementis. Many of the 

 forms have an old-world look, and exhibit minute differences from 

 those of more recent times. Nearly all the Synedras are distorted, 

 apparently by pressure. 



Cell-Division in Melosira.J — The previous investigations of Dr. 

 0. Miiller on the mode of cell-division in Terpsinoe musica, led to the 



* Bull. Torrey Bot. Club, xii. (1885) pp. 1-6 (1 pL). 



t Sci.-Gossip, 1885, pp. 36-7 (3 figs.). 



X Ber. Deutsch. Bot. Gesell., i. (1883^ pp. 35-44 (1 pi.). Priugsbeim's 

 Jahrb. f. Wiss. Bot., xiv. (1883) pp. 232-90 (5 pis.). See Bot. CentralbL, s.vi. 

 (1883) p. 194. 



Ser. 2.— Vol. V. 2 K 



