86 TUFTS COLLEGE STUDIES, VOL. IV, No. 7 



Page 368, HORHISCIA, first line, cancel all in first paragraph 

 after "several pyrenoids," and substitute, 



Asexual reproduction by macrozoospores, many in a cell, 

 obovoid, extending into a long projection below, and with 4 

 cilia above ; also by microzoospores in still larger numbers in a 

 cell, with 4 cilia and red stigma, but with less conspicuous pro- 

 longation below ; also by akinetes formed by the breaking up 

 of the filaments into individual cells, with thick wall, either 

 producing new filaments or zoospores ; sexual reproduction by 

 small male and larger female 2-ciliate gametes (Wille, 1909, 

 p. 115) ; also by isogamous 2-ciliate gametes (?). 



Page 369, after note on HORMISCIA WORMSKJIOLDII, add, 



H, tctraciliata Frye & Zeller, 1915, p. 9, PI. II, seems to be 

 a synonym of this species. It has macrozoospores similar to 

 the zoospores of //. penicilliformis, also smaller 4-ciliate spores, 

 supposed by the authors to be gametes, but probably microzoo- 

 spores. Macro-and microzoospores are known in many genera 

 of green algae, but there is no record of 4-ciliate gametes in the 

 Cladophoraceae, and in other families they are quite excep- 

 tional. Their figure 20, " gametes fusing," would seem rather 

 to represent two imperfectly separated microzoospores. 



Page 372, for Key to the Species of Valonia, substitute, 



i. Frond bullate, unbranched. i. V. vtntricosa, 



i. Frond more or less abundantly branched. 2. 



2. Branches in whorls. 5. V. cottffrvoides. 



2. Branches not whorled. 3. 



3. Cells spherical, ovoid or pyriform. 6. V. tnacrofihysa. 



3. Cells cylindrical to clavate. 4. 



4. Cells distinctly clavate, rather stout. 2. / '. utriculosa. 



4. Cells nearly or quite cylindrical, slender, densely branched. 



3. V. aegagropila. 



Page 373, after description of VALONIA UTRICULARIS, add, 



Forma CRUSTACEA Kuckuck, 1907, p. 180; Borgesen, 1913, 

 P- 30, figs. 17-18; P. B.-A., No. 2074. Forming dense, crisp 

 lUiMM in shallow water, both in quiet pools and on exposed 

 reefs. Bermuda, Virgin Islands. Enrofx. 



P*g 373 after V. VERTICILLATA, add, 



V. vtrticillala is made the type of a separate genus, 



KRNODESMIS Borgesen, 1912, p. 259. 



Frond with erect main axis, attached by rhizoids, claviform, 

 annulately constricted near base, apex obtuse, bearing a whorl 



