Cavernularid from Ceylon. 563 



small portion. They vary to a considerable extent in the 

 different parts of the colony, but a few characteristic points 

 may be noted as common to all. In certain respects they 

 resemble sponge-spicules more than the typical Alcyonariau 

 forms, especially in the fact that they are hyaline and smooth. 

 Many, however, bear digitiform processes, though they could 

 in no way be termed echiiiulate or warty. In many cases 

 the terminal processes do not end bluntly, but present the 

 appearance of attached cylinders. In the bifurcated forms 

 they closely resemble a double-barrelled gun. Another 

 noteworthy point is the characteristic annulated structure 

 most prominent on the cylindrical forms or those with 

 cylindrical terminations. 



A detailed examination of the spicules reveals remarkable 

 peculiarities ; those of the cortical layer of the stock are 

 arranged in small groups^ which give the colony the warty 

 appearance already referred to. They include the following 

 types : — 



[a] Blunt spindles, 0-3 x 0-05 to O'lo X 0*05 mm. 



{b) Sinuous cylinders, 0*3 x 0*025 mm. 



(c) Pyriform and elongated forms, 05 X 0*075 mm. 



{d) Double vases, 0*3 X 0*1 mm. 



(<) Club-shaped, with digitiform terminal processes, 0"3x 

 0*05 mm. 



(/) Others approaching a palmate form, 025x0075 mm. 

 (fig. 4). 



Those supporting the body-parenchyma of the stock include 

 the following types : — 



[a] Cylinders with processes at both ends^ 0'5x 0*075, 

 0-7x0*05 mm. 



[h) Sinuous, with digitiform terminations, 0'5x 0*1, 0'6 X 

 0*075 mm. 



(c) Club-shaped, with digitiform processes, 0*55 X 0'05 mm. 



[d] Double barrels, 0*5 x 0*05, 0*7 x 005 mm. 



{/) Forms like a long bone bereft of epiphyses, 0*4 x 0*02, 



0*5x0*02, 0*5x0-025 mm. 

 (/) Irregular and sinnous forms, 045 x 0*05 mm. (fig. 5). 

 Those of the trunk, which are on the whole larger than 

 those in the stock coenenchyma, include : — 



(a) Spindles, 0*8 x 0*1, 0*5 X 0*05 mm. 



[b) Palmate forms, 0*6 X 0-1, 045 X 0*05 mm. 



(c) Clubs, 0*55 XOOI mm. 



[d) Cylindrical forms, 0*45 x 0-025 mm. (fig. 6). 



An attempt to cut sections proved a failure, and it was 

 thought undesirable to sacrifice much of the single specimen, 

 which had already been cut into four pieces. 



