PROF. W. A. HEEDMA.N ON BRITISH TUNICATA. 441 



Hancock's descriptioa of this species reminds me strongly of 

 the rather handsome specimens of Ascidiella aspersa (aculeata 

 form) which are found in some parts of the Clyde district, e. g. 

 Lamlash Bay, and of which I give a figure (PI. XXXIV. fig. 1) ; 

 there is nothing in the appearance of Canon Normaa's specimen 

 to contradict the supposition that "^. Normani'''' may be 

 A. aspersa (0. F. M.). 



13. Cionafascicidaris, Hnk. — I have examined Canon Norman's 

 type specimens, collected by Mr. A. Gr. More in Kilkieran Bay, 

 Connemara; and there is no doubt that this is a good and 

 well-marked species. I now give some figures (see PI. XXXIII.) 

 of the external appearance and internal structure, and the fol- 

 lowing notes to supplement Hancock's description. 



The test has distinctly two regions (PI. XXXIII. figs. 1 & 2)— 

 the enlarged part at the posterior end, which is much firmer and 

 is roughened on the surface, and the remainder, over the greater 

 part of the body and anterior end, which is all very thin and 

 membranous. 



The union of individuals into clumps is effected entirely by the 

 interlocking of little papillose outgrowths from the test round 

 the posterior ends and a little way up the sides (PI. XXXIII. 

 figs. 2 & 3). 



The mantle is thin and transparent, but has the strong longi- 

 tudinal muscle-bands characteristic of the genus. The atrial 

 siphon is completely dorsal in position and at right angles to the 

 branchial. There is a long narrow pedicle connecting the anterior 

 part of the branchial sac with the visceral mass (PL XXXIII. 

 fig. 5) so as to divide the body into " thorax " and " abdomen ; " 

 but the branchial sac really extends down (though very narrow) 

 to the level of the stomach. The vessels of the branchial sac are 

 all very delicate. Papillae, and sometimes intermediate papillae, 

 are present. The stigmata are very wide, and are about 4 in a 

 mesh (PL XXXIII. fig. 4). 



The tentacles are numerous, slender, about 50 of various sizes 

 placed irregularly, but very closely (PL XXXIII. fig. 8). 



The dorsal languets are triangular, small, broad, and flattened 

 antero-posteriorly. 



The dorsal tubercle is irregularly elliptical in shape, and is 

 elongated transversely, with the aperture anterior and both horns 

 turned in. 



LINK. JOUEN. — ZOOLOGY, TOL. XXIV. 34 



