ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 341 



material and methods ; general morphology and histology ; origin and 

 development of the conceptacle ; origin and development of the crypto- 

 stoma ; spermatocyst ; oocyst ; and sporeling. Growth takes place from 

 a 3-sided apical cell, which gives rise to stem, branch and leaf structure. 

 The tissues contain much reserve material, partly oil, partly perhaps a 

 carbohydrate. Conceptacles and cryptostomata originate in a single 

 flask-shaped initial cell, which divides at first into two dissimilar seg- 

 ments — a large lower cell which gives rise to the walls of the conceptacle 

 or cryptostoma ; and an upper cell, the " tongue " cell, which either 

 remains inactive, or divides to form a short filament, or degenerates. 

 The author holds the view that cryptostomata have been derived from 

 conceptacles, whose sexual organs have become sterile. The oocyst 

 normally gives rise to but one egg. 



New American Coralline Algae.* — M. Foslie and M. A. Howe 

 describe seven new species and four new varieties of Corallines, from 

 various parts of the West Indies. In some of the species described the 

 material is entirely sterile, and in others empty conceptacles have been 

 found. But the plants possess such well-marked distinctive characters 

 in outward form or internal structure that the authors consider the 

 descriptions and photographs will prove sufficient for identification. 

 Photographs are given of the habit and structure of the various species 

 and varieties. 



Morphology of Caulerpa.f — J. M. Janse gives an account of his 

 studies of the polarity and organ-formation in Caulerpa prolifera. He 

 treats his subject under the following headings : (1) Polarity and 

 streaming of protoplasm as occurring in branchlets, either wounded or 

 reversed ; (2) Polarity and organ-formation, firstly the formation of 

 new members, such as branchlets, rhizome, rhizoids ; and secondly 

 changes in the protoplasm during the formation of new growths ; 

 (3) Theoretical considerations. A full summary is appended. In brief, 

 Caulerpa prolifera exhibits a well-marked polarity, which is seen both 

 in the course of the stronger protoplasmic streams in intact and in 

 wounded branchlets, and also in the formation of organs as the result of 

 severe wounds. 



Regeneration in Polysiphonia.J — F- Tobler has studied the question 

 of regeneration and polarity in Polysiphonia (4 species) and Geramium 

 (3 species). After describing his method of treatment, he passes on to 

 discuss the artificial control of growth in uninjured specimens, including 

 unequal growth in definite parts, adventitious shoots, rhizoid-formation ; 

 next, growth in injured specimens (the shedding of parts followed by 

 regeneration) ; and finally, the question of polarity. 



Complementary Chromatic Adaptation of Algse.§ — M.Graidukov gives 

 an account of some most instructive experiments made by him on Porphyra 

 laeiniata Ag. and Phormidium temie Gom. The apparatus and methods 

 of work are described and the following results are arrived at. The 



* Bull. New York Bot. Garden, iv. (1906) pp. 128-36 (14 pis.). 



t Jahrb. wiss. Bot., xlii. (1906) pp. 394-460 (3 pis.). 



% Tom. cit„ pp. 461-502 (3 pis.). 



§ Ber. Peutsch. Bot. Ges., xxiv. (1906) pp. 1-5. 



