CATALOGUE OF TUNICATA. 21 



Locality. Port Jackson and Port Stephen ; nearly a dozen 

 specimens. 



I have formed this species for the reception of a number of specimens 

 which vary somewhat amongst themselves, and which seem in most 

 respects rather closely allied to Microcosmus Julinii, von Drasche ; but 

 which, on the other hand, I feel somewhat inclined to remove from the 

 genus Microcosmus, and place in the genus Bhabdocynthia, alongside 

 R. complanata, Herdm. 



The specimens are all of large size. The largest is the one from 

 Port Jackson, whose measurements are given above, and which is 

 figured about half natural size in fig. 1 (PI. Cyn. III.). The test in this 

 specimen is tough, leathery, and of a rich dark-brown colour on the 

 outside, as if it had been tanned or tarred externally. The posterior 

 end of the test is provided with a number of tufted, branched processes 

 or tags for attachment (fig. 1). When this test is cut open, however, 

 it is found that nearly the posterior half (6'5 cm.) is solid, and so 

 the space left for the body is much reduced (see fig. 2). Another large 

 specimen is attached to the posterior end of a large Ascidia, and bears 

 in its turn four specimens of Polycarpa belonging to two species (PI. 

 Cyn. IV., fig. 1). It is of a distinctly lighter-brown colour, and has 

 the siphons or projections bearing the apertures relatively longer and 

 narrower, but the internal structure is much the same. Then there are 

 three larger specimens (between 12 cm. and 18 cm. in length) closely 

 resembling the last, but more or less covered externally with colonies of 

 a Leptoclinum and many other smaller animals. 



There is a specimen from Port Stephen measuring about 7 - 5 cm. in 

 length and 6 - 5 cm. in breadth, so that the form is nearly discoidal ; and 

 finally, there are half-a-dozen other specimens of varied shape and 

 colour, extending from 12 cm. down to about 6 cm. in length. 



With the exception of the very dark specimen (PI. Cyn. III., fig. 1), 

 the prevailing colours throughout the species are those bright yellows 

 and ruddy browns which are already known in several other members 

 of the genus. In the anterior part of the body the test is thin but 

 tough, and it is seen in sections (fig. 4) that the projections on the 

 surface are not mere folds, but are permanent outgrowths. The 

 remarkable thickened part of the test forming the posterior half of the 

 body in one specimen (fig. 2) is very soft, and spongy in texture. The 

 large apertures are square, 4-lobed, or cross-slit in shape, according to 

 the state of contraction. When the test is removed the siphons are seen 

 to be very muscular and very long. They may be as much as 3 cm. in. 



