ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 65 



Perisprrmon g. n. Similar ; but auxiliary cell and carpogone termi- 

 nal on one filament, one above the other; auxiliary cell developing into 

 a 1-spored gonimoblast ; male elements surrounding the female in one 

 conceptacle. ■ 



CEdogoniaceae.* — Karl E. Him has brought out a magnificent and 

 splendidly illustrated monograph of this family of Algae. After a 

 minute and exhaustive general description of the various parts, the three 

 genera. (Edogonium, Bidbochsele, and CEdocladium, are taken in succession. 

 Of (Edogonium, 199 species in all are described, but of these 43 are but 

 imperfectly known, or their organs of reproduction have not yet been 

 accurately observed ; 38 are now described for the first time. Of Bulbo- 

 clisete 41 species are described, six of them new ; CEdocladium is mono- 

 typic. The monograph is one of the most complete published of any 

 family of Algae. 



Fertilisation of Sphseroplea.f — M. Golenkinhas afresh investigated 

 the mode of fertilisation in Sphseroplea annulina, a form allied to Klc- 

 bahn's var. latisepta, having both uuiuucleated and multinucleated 

 oospheres. It presents some differences from the mode observed in any 

 other alga?, indeed in any other plants, but resembles that in the 

 ( 1 hlarnydomonadineae. 



Nuclear division was followed both in the antherid and in the vege- 

 tative cells. The nucleolo breaks up into a number of fragments, which 

 arrange themselves in a nuclear dis-k, and then appear to split up and 

 move to the two poles, where they fuse into daughter-nucleoles. All 

 the chromosomes of the dividing nucleus appear to originate from 

 the nucleole. This fusion of the nucleoles in Spirogyra and in the 

 I 'hlamydomonadincae (as Dangeard has shown) indicates that they are 

 not true nuclei, but carriers of chromatin substance. Nucleoles of this 

 kind occur also in a large number of green algae, including all Volvo- 

 cineae, also in Musci. A similar process takes place iu Amoeba hyalina. 



The septa of Spliseroplea exhibit at certain spots a kind of acrolation 

 presenting an appearance of sieve-disks, but no continuity of protoplasm 

 from one cell to another could be detected. 



Division of the Oosphere in Cystosira. j — H. Winkler has carried 

 out a series of experiments for the purpose of determining the influence 

 of external factors on the direction of the first division-wall in the 

 impregnated oosphere of Cystosira, barbaia. He established that the 

 direction was quite independent of a difference in the supply of oxygen 

 to the different sides of a germinating oosperm, to gravitation, or to 

 contact. On the other hand, light w r as found to have a distinct inHuenco 

 on the first division ; the first septa in all the germinating plants were 

 nearly paiallel to and vertical to the direction of the mcidtnt light. 

 When this polarity has once been established, it cannot be reversed. 



Structure of the Diatom Girdle. § — As the result of observations, 

 T. (J. Palmer and F. J. Keeley have come to the conclusion that the 



* Act. Soc. Scient. Fennkrc, xxvii. (1900) iv. and 391 pp., 64 pis. and 27 figs. 

 (German). 



t Bull. Soc. Imp. Nat. Motcou, 1899 (1900) pp. 343-61 (1 pi.) (German). Cf. 

 this Journal, 1899, p. .514 



X Ber. Deutscli. Bot. Gcs., xviii. (1900) pp. '297-305 (1 fig.'). 



§ Bine. Acad. Nat. Sci. i l.uiidelphia, 1900, pp. 405-79 (-.: pis.). 

 Feb, :.>0.h, 1901 F 





