ECTEINASCIDIA AND THE CLAVELINIDjE. 151 



less marked, and the internal longitudinal bars less com- 

 plete than in Bh. neapolitana. 



So much for the previously described species of this 

 interesting group : I now turn to some new material. A 

 few years ago Mr. T. J. Moore, curator of the Liverpool 

 Free Public Museum, placed in my hands for examination 

 a small group of " social" Ascidians, dredged by Captain 

 A. Browne, in Alexandria Harbour, from a depth of 3 — 5 

 fathoms. I saw at once that this form belonged to Ectein- 

 ascidia in the wide sense, and was closely allied to E. 

 turbinata, but the pressure of other work prevented me 

 from examining it more minutely until lately, when I 

 found that it was undoubtedly a new species of Ectein- 

 ascidia in the restricted sense, as employed by Van 

 Beneden. 



A few days ago I received from Mr. E. Thurston, 

 Superintendent of the Government Central Museum, 

 Madras, a small group of "social" Ascidians, dredged 

 from the pearl banks in the Gulf of Manaar, with the 

 request that I would investigate it. Upon examination it 

 proved to be also a new species of Ecteinascidia, closely 

 allied to E. turbinata, but distinct. The description of 

 these two additional species is as follows : — 



1. Ecteinascidia thurstoni, n. sp. (PL VI, figs. 1 — 9) 



External appearance : — A large number of Ascidiozooids 

 are found united together by a delicate branched stolon, 

 which is fixed to the stem of a Hydroid Zoophyte (see PI. 

 VI, fig. 1). The Ascidiozooids are closely placed on the 

 stolon, so as to form a thickly-clustered mass. Each 

 Ascidiozooid is of an elongated ovate or almost cylindrical 

 shape, somewhat compressed laterally and tapering towards 

 the posterior end (PL VI, figs. 2, 3) where it joins the 

 stolon by a very narrow pedicle. The anterior end is trun- 

 cated or flat, and bears at its extremities two small but 



