HYDROIDA. 109 



HYDROIDA. 



Sub-order T. : ATHECATA. 

 Family: TURRID/E. 



Corydendrimn chevalense, n. sp. Plate I., fig. 4. 



Trophosome. Colony reaching the height of ^ an inch, with a simple or branched 

 stem of a pale straw colour, slightly wrinkled, but never ringed. Branches lying 

 alongside the stem for a short distance near their origin, then diverging ; very much 

 twisted and entangled (see Plate I., fig. 4). Hydranths varying in size, those on 

 unbranched stems the largest, with about 18 tentacles scattered on the upper -f of 

 their leno-th. 



Goxosome. Medusiform gonophores on short peduncles, springing singly or 2 or 3 

 near one another, often 2 opposite, on both sides of the stem, between the origin of 

 the branches and the hydranth. 



Locality : On Pec ten shells and on sea-weeds from the Cheval Paar, Gulf of 

 Manaar, 6 to 8 fathoms. 



From indications in the gonophores, which vary much in their stages of develop- 

 ment on the same specimen, the manubrium appears to be four-lipped, the radiating 

 canals four, and the tentacles many. The form of the medusa of Corydendriunx has 

 not yet been traced, and the one species, C parasiticum, Cavolini, has now 

 remained so long imperfectly known that it seems doubtful whether its description 

 will ever be completed. In the meantime it seems better to place the present species 

 here rather than to form a new genus or to place it with Tuvris, only known as an 

 unbranched form. 



The fully developed trophosome of Tunis has, however, not yet been seen. If, 

 therefore, the further development of the present gonophores should lead to their 

 identification with those of Tun-is. as appears possible, then this species will require 

 to be transferred to that genus, the definition of which will be altered so as to include 

 simple or branched forms. 



Family : BOUGAINVILLID^E. 

 Boug-ainvillia, sp. 



This is not recognisable as any known species, and there is not sufficient material 

 to enable me to describe it fully as a new species. One peculiarity of the form is 

 that the branches have frequently blunt-ended tendrils growing from them. 



Locality : Found growing among colonies of a Campanularian (Obelia austrcdis) 

 from the Cheval Paar, Gulf of Manaar, G to 8 fathoms. 



