ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 323 



nor final, since many genera of the green algse are still in need of a 

 clear systematic investigation. 



Antarctic Marine AlgSB.* — A. and E. S. Gepp dnd Madame Paul 

 Lemoine publish a report on the small collection of marine algae 

 collected by the "Terra Nova" Expedition to the Antarctic in 1910. 

 The former authors record eighteen species, the most interesting of 

 which is CJinjsymenia ohovata from South Trinidad, previously only 

 known from the southern and western coasts of Australia. The 

 opportunity is taken to point out the probable identity of the author's 

 unknown " Floridea," collected by Dr. Rudmose Brown in the South 

 Orkneys in 1903, with the Cur dim Racovitzse Hariot, collected by the 

 French Antarctic Expedition and published in 1912. The Melobesieie 

 of the " Terra Nova " Expedition are determined by Madame Paul 

 Lemoine. Only two species were found, and both are new : the one 

 dredged from a depth of 30 m. oft" the North Cape of New Zealand, 

 iind the other from South Trinidad. The habit and structure of both 

 species are fully described and figured. 



Fungi. 



(By A. LoRRAiN Smith, F.L.S.) 



Study of Saprolegnia.f — P. A. Dangeard describes the nature and 

 habitat of this genus of aquatic facultative parasites. In order to 

 determine the species it is necessary to have the sexual organs ; the 

 species he experimented with bore no oogonia, so it is only doubtfully 

 that he refers it to S. ferax. 



He found that the cytoplasm formed a parietal layer, the centre of 

 the filament being occupied by a long vacuolar canal. This parietal 

 layer is thicker at the extremity of the branches, or the tips may be 

 entirely full of cytoplasm. It is homogeneous and colourless, and 

 contains minute refracting spherules or microsomes, mixed with 

 oleaginous globules. The nuclei are spherical or ellipsoid and refractive, 

 particularly the large nucleolus. There are also present in the cytoplasm 

 other bodies in the form of spheres, rods or long filaments refractive 

 and homogeneous ; these he considers to be " mitochondries " or 

 " chondriocontes." Dangeard gives the results of his experiments in 

 staining the cytoplasm and these various bodies, and he discusses their 

 origin, their activity, and their relation to the plant. 



Endothia parasitica and Related Species. | — Great attention has 

 been given to this fungus since it originated the epidemic of canker 

 disease of the chestnuts in America, and there has been considerable 



* British Antarctic (" Terra Nova ") Expedition, 1910. Natural History Report, 

 Botany, pt. ii. (London, 1917) pp. 17-28 (figs.). 



t Bull. Soc. Mycol. France, xxxii. (1916) pp. 87-96. 



X U.S. Dept. Agric, Bull. No. 380 (1917) 82 pp. (23 pis. and figs.). 



