ACTINIANS OF GULF OF CALIFORNIA— CARLGREN 



427 



pet. No distinct sphincter. Tentacles smooth, ordinarily long, nu- 

 merous, up to about 192, hexamerously arranged. Two narrow 

 siphonoglyphs. Six pairs of perfect mesenteries, two pairs of di- 

 rectives. Considerably more mesenteries at the margin than at the 



Figure 80. — a, Aiptasiomorpha elongata, new species, retractor, b, c, Telmatactis 

 panajnensis (Verrill) : b, Upper part of sphincter; c, part of mesentery with pieces of 

 discontinuous filament (black) and acontia. d, Calliaciis variegata Verrill, lower 

 part of sphincter. 



limbus. Distribution of gonads unknown. Retractors bandlike 

 (fig. 80, a). Perietobasilar muscles weak. Nematocysts of the 

 column 13-17.6 by 4.2 (4.5) fx (microbasic p-mastigophors) ; those 

 of the tentacles partly 15.5-21 by 2.8-3 p. (basitrichs, few), partly 

 19.7-24 by 3.5-4.5 jx (microbasic ^^-mastigophors or amastigo- 

 phors) ; those of the actinopharynx partly 21-26 by 2.8 /a (basit- 

 richs), partly 24-29.6 by about 4.2 /x (probably microbasic ja-mas- 

 tigophors) ; those of the filaments partly 27.5-32.4 by 4.2-4.5 /x 

 (probably microbasic 2>mastigophors), partly 11.3-14 by 4.2-4.5 ^ 

 (microbasic p-mastigophors) ; those of the acontia partly 39.5-53.6 

 by 6.3-9.5 /x (probably microbasic p-mastigophors), partly 14-18.3 

 by 2.2-2.5 /x (basitrichs). 



Measurements. — The largest specimen, length 3 cm., greatest 

 breadth 1.8 cm. 



Holotype. — San Carlos Bay, Sonora, Mexico, March 30, 1940. 



