72 



BULLETIN" 100, UNITED STATES NATIONAL MUSEUM. 



APSTEINIA PUNCTATA fForskSl, 1775). 



Salpa punctata Forskal, 1775. 



S. punctata Vogt, 1854. 



S. musculosa Herdman, 1888. 



We have had for study four specimens of the solitary form of this 

 species and five of the aggregated zooids, besides the well-developed 

 zooids on the stolons of two of the solitary indi- 

 viduals. Specimens of both solitary and aggre- 

 gated forms have been deposited in the United 

 States National Museum. 



Cat. No. 8463 U.S.N.M. (solitary form), from 

 Naples Zoological Station; one specimen. 



Cat. No. 6464, U.S.N.M. (aggregated form), 

 from Naples Zoological Station ; four specimens. 



Careful comparison of our specimens has shown 

 Streiff's work so accurate that for the muscula- 

 ture we use mostly his figures. 



APSTEINIA PUNCTATA, solitary form. 



There are eight body muscles (figs. 48 and 49), 

 all broad complete bands except the eighth, 

 which is interrupted ventrally at the sides of 

 the gut, as the homologous muscle is in the 

 Cyclosalpas and, of course, the Ritterias. The 

 intermediate muscle and body muscles I and II 

 are in contact dorsally. The edges of all the body muscles are 

 composed of wide fibers (fig. 51). The central fibers are much 

 narrower. The bands thus appear lighter on each edge. 



FlQ. 48.— APSTEINIA PUNC- 

 TATA, SOLITARY FORM, 

 DORSAL VIEW SHOW- 

 ING muscles. From 

 Strieff (1908). 



FlQ. 49.— APSTEINIA PUNCTATA, SOLITARY FORM, VIEWED FROM THE RIGHT SIDE. X 2 DIAMETERS. 



(Drawn by Hoyt S. Hopkins.) 



The oral muscles (fig. 51) include a dorsal retractor and a ventral 

 retractor which posteriorly is bifurcated, its dorsal division running 

 back along the side of the body in a horizontal plane, reaching beyond 

 the posterior edge of the seventh body muscle (figs. 48 and 49). Its 



