106 UNITED STATES NATIONAL MUSEUM BULLETIN 251 



ard formula of the arrangement of tentacles. Larger tentacular ring 

 situated far posterior to ring comprising medium and smaller tentacles. 

 Ciliated groove elongated, this shape differs distinctly from that of 

 G. fecunda and C. fasciata^ in which the groove is a crescent cleft laid 

 transversely. Dorsal languets long, located along dorsomedian line, 

 horizontal membranes well developed along respective transverse ves- 

 s^els. Cardiac end of stomach situated approximately at posterior 

 quarter of abdomen. Stomach elongated, with four longitudinal 

 ridges including typhlosole; its surface quite smooth. Hind stomach 

 very short, midintestine indistinct. Circumintestinal gland consists 

 of many whitish tubules irregularly creeping in range between pos- 

 terior end of hind stomach and middle of stomach. Formation of 

 fecal pellets observable only in proximal part of ascending l)ranch 

 of intestinal loop. Anus opens at dorsoposterior corner of thorax, 

 slightly posterior to last stigmatal row, bilobed, margin of each lobe 

 plain. Testicular follicles small and very numerous, probably 200 

 or more in a fully mature state; usually distributed on left side of 

 intestinal loop posterior to middle of stomach, although a few may 

 also be found on right side in a fully mature state. Ovary situated 

 near the center of gonad. 



Remarks. — Sluiter (1904) and Van Name (1918) mention that 

 there are transverse muscles on the thoracic mantle, but no such mus- 

 cles were found in examined zooids of the present colonies. In the 

 point that only the longitudinal muscles are defined on the thoracic 

 mantle, the present specimens closely resemble Stereoclavella avMralis 

 or Stereoclavella sp. described by Herdman (1899), but the colora- 

 tion of the present specimens seems to differ considerably from that 

 of Herdman's species. Glavelina coerulea Oka known from Kyiisyu 

 Island, Japan, also closely resembles the present specimens in the 

 structure of the zooid, but respective zooids are connected to the stolon 

 individually and fusion between the abdominal portions, or bundle 

 formation of zooids is unknown. 



Distribution. — NW. Australia and the Great Barrier Reef 



45. Clavelina (Synclavella) arafurensis Tokioka 



Figure 36 

 Clavelina {Synclavella) arafurensis Tokioka, 1952, p. 97, fig. 5. 



MATERIAL EXAMINED 



Palau Islands : Iwayama Bay, east side of Oyster Pass ; GVF 220. One small 

 colony consisting of two cormidia (USNM 11444). — Iwayama Bay, month of 

 Oyster Pass ; GVF sta. 236A. One large colony (USNM 11426) . 



Description. — A large colony, consisting of many cormidia (USNM 

 11426) and a small one consisting of two cormidia (USNM 11444) 

 from the Palau Islands were examined. 



