ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 469 



Ralfs's " British Desmidiacese " and in the works of the older authors 

 be very doubtful. (3) The following earlier specific names have 

 priority, and must be retained : Glostenum Libellula Focke (if removed 

 from Penium) and Desmidium cyliiidricum Grev. (Didymopriwn Ralfs, 

 1845). Three other short notes are entitled " Aphanoclnete or Her- 

 posteiron," " Tribonema or Conferva," and " Myxonema or Stigeo- 

 clonium." The paper is in English. 



Sphaeroplea annulina * — K. Meyer has made a study of the develop- 

 ment of this alga, especially as regards the germination of the oospore, 

 the formation of the zoospores, the spermatozoids, and the egg-cells ; he 

 has also studied the systematic position of the species. The author 

 gives a detailed description of the development of the antheridia and 

 oogonia, and then proceeds to the oospore and its germination. This 

 may take place according to one of two different types, and both are 

 described : the number of zoospores is always four, and not, as other 

 authors have suggested, a varying number. As regards the systematic 

 study of S. annulina, the author finds that the recognised varieties- 

 (formerly regarded as species) are so uncertainly defined, and the species 

 itself is so variable, that he considers there is only one species of 

 Sphceroplea, S. annulina, with two extreme forms, Braunii and crassi- 

 septa, and a series of intermediate forms between. 



Subterranean Algal Flora of France.f — J. Maheu has made a study 

 of the entire flora of the caves, wells, and other subterranean localities 

 of France. The environment is not conducive to the development of 

 algge, those most commonly represented being species of Hwmatocoecus, 

 Protococcus, Palruellacese, and Diatoms. The species are poor in chloro- 

 phyll, reduced in size, and sometimes so polymorphous as almost to 

 constitute new forms. The author notes that the colour of certain 

 species varies from green to red, according to the degree of darkness in 

 which they live, and while some genera cannot live without a certain 

 amount of light, others are able to develop in total obscurity. This 

 paper includes some interesting observations on the occurrence of bac- 

 teria in subterranean streams, and the influence on public health that 

 these are able to exercise throughout a large area. 



Protococcoidea34 — C. E. Bessey continues his work on the structure 

 and classification of alga3, and in the present paper he deals with the 

 Protococcoideas, prefaced by a key to the four orders of Chlorophyceas. 

 Keys are given to the families and genera of Protococcoideas, and the 

 relationships of the genera in each family are indicated by diagrams. 

 Each genus is described, and measurements of the cells are given. 

 Other classifications of the green alga are discussed and compared in 

 tabular form, notably those of Engler, Blackmail and Tansley, West, 

 and Oltmanns. Then follow remarks on the relationship of the green 

 algse to the lower animals, and a chart to show the mutual relationship* 

 of the genera of Protococcoideas. 



* Bull. Soc. Imp. Nat. Moscow, xix. (1906) pp. 60-84 (2 tables). 



+ Ann. Sci. Nat., ser. 9, iii. (1906) pp. 93-8. 



X Trans. Amer. Micr. Soc, xxvi. (1905) pp. 121-36 (1 chart). 



