F u i: s ii . w \ T i: u A L G JE o v T H K r x i T i: i> STATE s. 179 



centre. The spermato/.oids, which arc at this time already free in the water, are \cr\ 

 minute, longish, ellipsoidal or ovate masses, provided with two unequal cilia. These 

 commonly l)otli arise together from one end of the body, and arc directed in oppo- 

 site directions one backwards, tlie other forwards. According to M. Wai/, how- 

 ever, in T. *<//',,/ the <ilia arise from the opposite ends. According to De Bury, 

 the spermato/oids of V. aversa, llassall, contain reddish pigment-grannies. M. 

 Wai/, states that he has twice seen the process of impregnation in V. neriwa, Lyngb., 

 and describes it essentially as follows: After the bursting of the antheridium and 

 tin formation of the opening in the oogonium, the spermatozoid clustered around the 

 little orifice in the latter, but were apparently debarred entrance by the presence of 

 a glutinous jelly. After a time, however, one, and then another, forced a passage 

 through this obstacle until finally a number gained access to the protoplasmic ball 

 within. Over this they swarmed, pushing it and retiring and butting against it 

 until some of them actually forced their way into it and were absorbed by it. Im- 

 pregnation being how completed, the oospore acquired a very sharp definite outline, 

 and secreted in a very short time a membrane around itself. The changes which 

 followed during its maturing consisted of the acquiring of a thick coat and the 

 replacing of the chlorophyl within by a reddish-brown coloring matter. The ripened 

 resting spore of almost all the Vauchcria is provided with three coats, of which the 

 middle is the thickest. The contents consist of protoplasm, reddish-brown pigment, 

 and numerous oil globules. 



Genus VAUCHERIA. 



Genus unicum, character idem ac faiuilisc. 



The only genus of the family, having the same characters. 



V. sessilis, (VAUCH.) DE CANDOLLZ. 



V. laxe intricata, pallide et suhsordide viridis; thallo capillari, parcc ramoso; oogoniis 3-3 

 approximates, rarias singulis, ovatis vel ovaH-oblongis, plus minusvc obliquis, rostratis; anthc- 

 riilin iiiirniii'ilin, rarnuli niodo brevi hamato, modo recto snbuluto, subclavato, modo clongato 

 et incurrato, hand raro circiuato sustentato; oosporis maturis fusco-puuctatis, ineinbruna 

 triplici involutis. (R.) 



Syn. V. sessilif, (VAUCU.) DK CANDOLLR. RABENIIORST, Flora Enrop. Algar., Sect. III. p. 



267. 

 V. ctespitosa, (VAUcn.) AOARDII. RABEMIOIIST, loc. cit. 



IIili. Salem, North Carolina; Sclnvcinitz. Common at West Point, New York ; Waterville, 

 Maine; Calpepper Co., Va. ; Bailey. % 



Laxly intricate, pale and subsordid green ; thallus capillary, sparsely branched ; oogonia 2-3, 

 approximate, rarely single, ovate or oval-oblong, more or less oblique, rostrate; anthcridia 

 intermediate, sustained upon branches partly shortly hamate, partly straight subulate, sub- 

 clavate, partly elongate and incurved, and not rarely circinnate ; oospores at maturity, fns- 

 cous-punctate, surrounded by a three-fold membrane. 



Remark. I think I found this species near Philadelphia in my earliest re- 

 arijches, but cannot speak certainly, having preserved neither notes nor specimens. 



