CHLOROPHYCE^E 155 



sent us with a case of a spore (gametangium) 

 borne not in a sporangium as in Acetabularia, but 

 free on its branch. One may regard this spore, 

 however, in the light of a sporangium which omits 

 to form spores and itself gives rise directly to 

 gametes, and this view is much strengthened by 

 comparison with the case of Botryophora and 

 Bormtella, where there is an actual sporangium, with 

 spores of similar origin, though we do not know 

 from observation what the fate of these may be. 

 Dasycladus by itself appears to exhibit perpetual 

 production of sexual generations, while in Accta- 

 bnlaria it is this generation that remains unde- 

 veloped, and is represented only by the spores 

 (gametangia). Such interpretations, however, must 

 remain purely speculative until further light is 

 thrown on the matter by an examination of the life- 

 history of such forms as Botryophora (so near 

 Dasydadus), Neomeris, Bometella, and Cymopolia. 



The Geographical Distribution, like that of Aceta- 

 bulariece, is in tropical and subtropical seas. Dasy- 

 cladus has one species occurring in the Mediterranean 

 and the Canary Islands. Botryophora also has one 

 species confined to the West Indian region. Neomeris 

 has several species, one in the West Indies, others in 

 Madagascar, the Malay Archipelago, and the tropical 

 Pacific. Bornetella is Australian, and occurs also in 

 the tropical Pacific. Cymopolia barbata occurs in the 

 West Indies, the Canary Islands, and has been re- 

 corded from Cadiz, but not from the Mediterranean, 

 while C. van Bossei represents the genus in the 

 Malay Archipelago. 



