58 THE AUSTRALIAN MUSEUM. 



irregularly placed ; in other parts, on and near the folds, straight and 

 arranged in regular rows ; never regularly curved to form infundibula. 



Tentacles 12 to 14 in number, much branched, of different sizes, but 

 not regularly arranged. 



Dorsal tubercle rather simple, U-shaped, with a shorter horn turned 

 in and a larger one coiled out, placed in a deep peritubercular area. 



Locality. Port Jackson ; three specimens. 



I refer this species with a little hesitation to the genus Ascopera, 

 founded for two very remarkable and very large Ascidians obtained by 

 the "Challenger" Expedition to the south of Kerguelen Island in the 

 Antarctic Ocean at a depth of 150 fathoms. In appearance (PL Mol. I. , 

 fig. 10) the present animal suggests a dwarf form of the "Challenger" 

 Ascopera cjigantea ; hence the specific name. Externally it has more of 

 a Cynthiid than of a Molgulid appearance, and somewhat resembles 

 Molgula cczpiformis from British Seas. It is exceptional amongst the 

 Molgulidae in having practically no covering of sand or gravel, and in 

 being fixed by a peduncle ; but in both these characters it agrees with 

 the other two species of Ascopera. The irregularity of the branchial sac 

 also, and the absence of curved stigmata arranged in spirals or infundi- 

 bula (fig. 12) is noteworthy. Our figure shows one of the more irregular 

 parts where the stigmata are all small. The figure shows also another 

 interesting feature, viz., imperfect or budding internal longitudinal bars 

 (fig. 12, i.l' .). Such are known in Corella and elsewhere in the family 

 AscidiidaB, but have not been previously described in the Molgulidge. 

 This goes far, in my opinion, to establish the real identity of nature of 

 the internal longitudinal bars throughout the Ascidise simplices which is 

 apparently doubted by Lahille, Garstang, and others. In some places 

 the branchial sac between the bars has regular rows of straight stigmata 

 like those of a Cynthiid. When the test is removed (fig. 11), the body 

 is very globular and the siphons are most curiously shaped and are 

 directed quite away from one another. Figures 13 and 14 show the 

 dorsal tubercle and one of the much-branched tentacles. The horns of 

 the dorsal tubercle are in some cases more coiled. A large parasitic 

 Copepod was found in the branchial sac. 



[The following Molgulidse have also been recorded from Australian 



seas : 



CcBsira (? Molgula) parasitica, Macd., King George's Sound, 



C. (? M.)ficus, Macd., Shark Bay, 



C. (7 M.) pellucicla, Macd., Shark Bay, 



Molgula inconspicua, Stirnp., 



