418 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loi 



part of the body in order to find out if there is a physa or a pedal 

 disc proper. If the former is present, the species is an Andvakia; 

 if the latter, it may be referred to the family Isophelliidae. Al- 

 though it is very difficult to determine whether basilar muscles are 

 present in specimens having a small proximal end, and a mistake 

 could easily be made, I think the basal end is a physa. I do find 

 muscles resembling basilar muscles, but they seem to run together 

 with the parietal muscles, of which they may be the most proximal 

 part. Likewise, the families Andvakiidae and Isophelliidae are 

 closely related to each other. The species of the latter family have 

 very likely originated in forms having a physa, as do the 

 andvakiids. It is possible that the genus Capneopsis Duchassaing 

 and Michelotti is identical with Andvakia and that it is provided 

 with a physa, which the animal has usually drawn in. Capneopsis 

 solidago Duchassaing and Michelotti, like Andvakia parva Carl- 

 gren, seems to be attached to stones and shells but in A. parva 

 the physa is visible only when the animal is in motion. Perhaps it 

 is so with Capneopsis (which, according to authors, resembles 

 Edwardsia) , though it was adherent to rocks. Moreover, the two 

 species resemble each other very much in their exterior and in 

 their anatomy. I have mentioned (1934, p. 32) that the basilar 

 muscles are weak in C. solidago. I may have confused basilar 

 muscles with the lowest part of the parietal muscles. In that event 

 the genus may be called Capneopsis and the family Capneopsiidae. 



Family ALICIIDAE 



ALICIA BEEBEI Carlgren 



Alida beebei Carlgren, 1940, p. 211. 



The single specimen is considerably larger than the small type. 

 The nematocysts are also larger throughout. The microbasic 

 amastigophors of the vesicles are 67.7-84.6 by 10-11.3 /i, the 

 microbasic amastigophors 80.4-86.8 by 8.5-9.2 ^, the basitrichs 

 18.3-21 by 2.8-3.5 fx, the microbasic amastigophors of the tentacles 

 are 53.6-59.2 by 7-8.5 /x, the basitrichs 16.9-21 by 2.5-2.8 /x, the 

 nematocysts of the actinopharynx 43.7-66 by 6.3-7 fx, the micro- 

 basic amastigophors of the filaments are 35.2-45 by about 7 fi, the 

 microbasic 29-mastigophors 7-12.7 by 3.5-4 /;,. In my paper of 1940, 

 p. 212 line 4, "mesenteries 96" should be followed by " ; 6." 



Measurements. — Length of the column 8.5 cm., breadth of pedal 

 disc 6-7 cm., length of tentacles up to 12 cm., breadth up to 0.2 cm. 



Collecting record. — Puerto Escondido, found pelagic in tide pool, 

 March 26, 1940, 1 specimen. 



Additional distribution record. — Arena Bank, Baja California. 



