TUNICATA. 3.31 



Tentacle* 20 to 22 in number, of two sizes, placed a little irregularly (fig. 5). The 

 tentacles have large swellings at their bases, and the interior of the branchial siphon 

 is marked out into rectangular areas by slight depressions. 



Dorsal Tubercle of small size, horse-shoe-shaped (fig. 6). 



Gonads hermaphrodite, about 1 2 on left side of endostyle and six on right. Each 

 gonad has ova in the centre and two testes, one on each side (figs. 8 and 9). 



Locality: Station LXIX., outer Chilaw Paar, 8 to 11 fathoms; along with large 

 colonies of Leptocliimm. 



This is a handsome species which, from its hermaphrodite gonads, belongs to the 

 genus Gynandrocarpa and differs in internal structiire from all the described species. 

 It belongs to that section which Michaelsen would separate as the genus Eusynstyela, 

 and is allied to Sluiter's two species Gynandrocarpa maxima and G. latericius, both 

 obtained in Malaysian seas by the " Siboga " expedition. From G. maxima our 

 species differs in the smaller size of the ascidiozooids, in the arrangement of the 

 longitudinal bars of the branchial sac and in having fewer tentacles. From G. latericius 

 it differs in the details of the branchial sac (see fig. 4), and also in the dorsal tubercle 

 (fig. 6), which is more like that of G. maxima. In the tentacles our form agrees with 

 G. latericius, and it possesses also those curious long, coiled, thread-like outgrowths 

 from the mantle (fig. 7) to which Sltjiter has drawn attention. In. fact, the Ceylon 

 species, while possessing a characteristic branchial sac of its own, is in other characters 

 intermediate between the two " Siboga" species. It differs also in details of branchial 

 sac, dorsal tubercle, tentacles, &c, from both the species of Eusynstyela described by 

 Michaelsen, viz., E. tincta (Van Name) from Bermuda, and E. hartmeyeri from the 

 "Red Sea, Gulf of Suez, and African coast. 



I have great pleasure in dedicating this interesting form to my friend Sir 

 Everard im Thurn, K.C.M.G., who was Colonial Secretary and Lieut. -Governor 

 of Ceylon at the time of my expedition, and who did much to encourage and promote 

 scientific work in the colony. 



Other species of Polystyelidae have been found in far eastern seas and also in 

 the southern part of the Indian Ocean, on the Agulhas bank, but none of these are 

 closely related to the present species. 



Mv " Field-notes'' contain the following record as to the colour of this species when 

 alive : " March 20th, 1902, on outer Chilaw Paar, masses of coral and calcareous tubes 

 covered with colonies of Leptoclimim (white, pink, dark neutral tint, &c), and also a 

 large colony of a Polystyelid of a pink or pale-crushed strawberry tint over the 

 general surface with red apertures and a few red dots between the apertures; between 

 the ascidiozooids the test has a slight bluish-grey tint." 



Diandrocarpa bvakenhielmi, Mtchlsn., var. ceylonica, n. Plate VII., figs. 10 to 18. 



There are several colonies of a beautiful transparent Polystyelid from the Gulf of 

 Mannar which, from the condition of its gonads, falls, according to Michaelsen's system 



2 u 2 



