﻿400 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 102 



the uppermost coil of the ascending intestine; F**, F®, F', anchor the 

 intestinal spiral farther back. The spindle muscle is not attached 

 posteriorly. 



The first coil of the alimentary canal, beyond the end of the con- 

 tractile vessel, has a ringed structure as if it functioned as a gizzard. 

 The spiral is rather snarled but there are about 36 single coils. Well- 

 developed mesenteries anchor the esophagus laterally to the retractors. 

 A small coecum is present. 



The nephridia open on the same level as the anus and are not long, 

 reaching only to the origin of the retractors. 



The contractile vessel is a simple blind tube without trace of vilU. 

 The brain is relatively large with two conspicuous pigment spots. 



Color in alcohol a soft brown, lighter on the introvert. 



Type.—U.S.^M. No. 21214, March 20, 1940, E. F. Ricketts, 

 1 specimen. 



Type locality. — Point Lobos, Espfritu Santo Island, near La Paz, 

 Baja California. 



Subgenus Thysanocardia Fisher 



Tkysanocardia Fisher, 1950a, p. 551. (Type Phascolosoma procerum Mobius.) 



Diagnosis. — Retractors two; contractile vessel with numerous 

 simple or branched villi; no hooks; nephridiopores always in front 

 of anus. Included species are: 



catherinae (F. Miiller) pavlenkoi? (Ostroumov) 



hozawai (Sato) procera (Mobius) 



hyugensis (Sato) pugettensis Fisher 



macginitiei Fisher pyriformis (Lanchester) 



martensi (Collin) semperi (Selenka and de Man) 



nigra (Ikeda) zenibaken^is (Ikeda) 

 onagawa (Sato) 



Remarks. — The species of this section of Golfingia differ from all 

 others in the possession of numerous villi, or blind tubules, either 

 simple or branched, on the contractile vessel. There are two retractor 

 muscles arising in the posterior third of the trunk. The nephridia 

 alwa3^s open anterior to the anus. Back of the tentacles is a zone of 

 smooth thin skin bounded by a narrow collar. The skin is usually 

 pale sepia and is provided with darker small cylindrical papillae. 

 There are no hooks on the introvert. 



G. pavlenkoi (Ostroumov, 1909, p. 323) probably belongs in this 

 subgenus, as it is stated to be related to G. semperi and G. nigra. 

 The r^sum^ in German does not mention the villi of the contractile 

 vessel. The introvert is one-and-one-third the length of the trunk; 

 the trunk and introvert are uniformly covered with dark yellow 

 papillae, having a short cylindrical or rounded conical form; no hooks; 



