ACTINIANS OF GULF OF CALIFORNIA— CARLGREN 



417 



lacking. The mesenteries of the second cycle may have filaments. 

 Retractors of the perfect mesenteries very strong, reniform to 

 circumscribed, with high, branched folds (fig. 78, c). The parietal 

 muscles (fig. 78, d) are well developed but are not distributed on 

 the column. The mesenteries of the second cycle resemble the 

 parietal muscles of the primary mesenteries. Nematocysts of the 

 tentacles partly 10-15.5 by 1.5-2 fx, partly 19-26.8 by 2.2-2.5 ^ (both 

 basitrichs), those of the actinopharynx partly 24-26.8 by 2.8-3 /* 

 (basitrichs), partly 24-28 by 5-7 ix (microbasic 2>mastigophors), 

 partly 31-39.5 by 5.6-7 /^ (probably microbasic amastigophors) ; 

 those of the filaments 15.5-18.3 by 2.8-4 /x (microbasic jo-masti- 

 gophors) ; those of the acontia partly 15.5-18.3 by 1.5 ix (bas- 

 itrichs), partly 42.3-49.3 by 5.6-7 ^ (microbasic amastigophors). 



Figure 78. — a, b, Calamactis praelongtis, new species: a, Retractor; b, parietal muscle 

 of first cycle, c, d, Andvakia insignis, new species: c. Retractor of perfect mesen- 

 tery; d, parietal muscles, e, f, Anthoplcura doivii Verrill, sphincter of two speci- 

 mens, g, Bunodosoma californica, new species, sphincter. 



Measurements. — Length about 1.2 cm., breadth 0.4 cm. 



Cotijpes. — Two specimens, U.S.N.M. No. 49442, Gabriel Bay, 

 Espiritu Santo Island, April 12, 1940. 



Remarks. — The proximal end of one specimen is invaginated, 

 that of the other is visible. I have sectioned the most proximal 



