8 THE AUSTRALIAN MUSEUM. 



Stereoclavella sp. (?australis, Herdman), PI. Clav. II., figs. 58. 



External appearance. The colony consists of several individuals 

 adhering by their narrow posterior ends to a short thick irregular stolon. 

 The anterior end of each Ascidiozooid is relatively wide and irregularly 

 truncated. The body is elongated and distinctly divided into thorax and 

 abdomen. The apertures are close together at the anterior end. The 

 colour is grey. The length of an Ascidiozooid is 1-2 cm., breadth 4 mm. 



Test thin and transparent, rather thicker on stolon. 



Mantle thin and transparent, muscle bundles mainly longitudinal. 



Branchial sac delicate, transverse vessels all the same size. Stigmata 

 large and numerous. Horizontal membranes present. 



Dorsal lanyuets long, and closely-placed, triangular in form. 



Locality. Broughton Islands (No. 43). 



The specimen shown at PI. Clav. II., fig. 5, may possibly be a 

 detached piece from a larger colony, like that figured on the previous 

 plate ; but even then it is questionable whether it can be referred to the 

 same species, as the musculature of the mantle (fig. 6) and the proportions 

 of the dorsal languets (fig. 8) are a good deal different. This species, 

 treating it as a distinct one, seems closely allied to Stereoclavella 

 (Clarclina) oblouya, Herdman, from which it differs chiefly in the size 

 and shape of the dorsal languets. In S. oblong a they are short and 

 conical, and are placed about their own length apart*; while in the 

 present species they are long and triangular in form (fig. 8), having an 

 expanded base flattened antero-posteriorly, and tapering to a narrow 

 point ; the distance between them is only about a fourth of the length 

 of each languet. The languets are united at their bases by a 

 longitudinal band (fig. 8, d.l.), which is very different from the condition 

 shown (PI. Clav. I., fig. 10) in S. aicstmlis, where the stigmata are 

 uninterrupted round the dorsal edge of the sac. 



Several large opaque ova and young embryos were found at the 

 posterior end of the peribranchial cavity, close to the oesophagus, in one 

 of the specimens, which shows that the Ascidiozooids were adult 

 although possibly they may be only a fragment of a colony. 



[The following Clavelinidae have also been found in Australian seas: 

 Pcroplwra Hutcldsoni, Macdonald. 

 Ecteinascidia eitphues, Sluit. 

 E. psammodes, Sluit. 



Eliopalopsis crassa, Herdm., Ki Is., 129 faths. 

 Ii.fusca, Herdm., Banda, 17 faths.] 



' "Challenger" Report, Tart I., PI. XXXV., fig. 8. 



