ACTINIANS OF GULF OF CALIFORNIA— CARLGREN 429 



Additional distribution record. — Panama. 



Remarks. — The exterior is well described by Verrill. The ar- 

 rangement of acontia in the mesenteries of the second (and third) 

 order is apparently characteristic of the species. Figure 80, c, 

 shows part of the mesentery with pieces of the discontinuous fila- 

 ment (black on the figure) and acontia. A very similar arrange- 

 ment of the acontia is described by Panikkar (1936) in Phyto- 

 coetopsis ramunni Panikkar. It is possible, however, that a simi- 

 lar distribution of the acontia occurs also in other species of 

 Telmatactis but has been overlooked. In figure 80, h, I have illus- 

 trated the upper part of a sphincter of a medium-sized specimen. 

 The sphincter shows a tendency to stratification and recalls the 

 sphincter of a Telmatactis from the Great Barrier Reef. The 

 youngest mesenteries seem to appear somewhat earlier than the 

 corresponding tentacles. The largest specimen has only 78 ten- 

 tacles, but 92 mesenteries ; the mesenteries of the fourth cycle are 

 absent on one side of a directive. 



Verrill (1899c, p. 214) proposed a new genus, Phelliopsis, for 

 his species, but Fischer (1887, p. 412) used this name for Phellia 

 nummus Andres. However, the latter is not a Telmatactis. Ac- 

 cording to Verrill (1899c) the acontia are absent in panamensis, 

 but I think he overlooked them. 



Family HORMATHIIDAE 



CALLIACTIS VARIEGATA Verrill 



Figure 80, d 

 Calliactis variegata Verrill, 1869, p. 481. 



The exterior of the species is well described by Verrill. The 

 larger specimen is very flattened, almost cakelike. The sphincter 

 is strong and distinctly transversely stratified. In its upper part it 

 recalls rather strongly that of Cricophorus nutrix (Stuckey) inas- 

 much as the very elongate muscle meshes are separated from each 

 other by mesogloea balks running parallel with each other. The 

 lower part of the sphincter is illustrated in figure 80, d. The 

 nematocysts of the tentacles are about 20.5 by 2-2.5 /x (basitrichs, 

 very numerous) ; those of the actinopharynx 19.7-24 by 2.5-2.8 fi', 

 those of the filaments partly 10.6-12 by 1.5-2 ^ (basitrichs), 

 partly 19.5-23.3 by 4.2-5 /x (microbasic ?)-mastigophors) ; those 

 of the acontia 19.7-24 by about 2.8 /x (basitrichs). 



Measurements. — The larger specimen, breadth of pedal disc 3 

 by 3.5 cm. 



Collecting record. — Concepcion Bay, March 27, 1940, two speci- 

 mens from a large conch housing a hermit crab. 



