284 



CEYLON PEARL OYSTER REPORT. 



appearance, which in the upper portion gives place to a streaked appearance due to 

 the larger spicules being disposed for the most part longitudinally. 



The lowest branches, two in number, are flattened from above downwards, and are 

 bent downwards so as to hide the upper portion of the trunk. The other branches 

 are more or less cylindrical and rise at right angles to the stem, the uppermost being 

 directed obliquely upwards. The secondary branches give rise to the twigs which 

 bear umbels of 6 to 8 divergent stipitate polyps. 



The lower portion of the stem has a yellowish-white colour, the upper portion of 

 the stem and the branches are yellow, while part of the twigs and the polyp spicules 

 are brick red to dull red in colour. Several of the spicules consist of a colourless 

 sheath surrounding a central core of a deep yellow to orange-yellow which extends for 

 about half the length of the spicule. 



The spicules vary very much in the specimens. The " Stiitzbiindel " spicules vary 

 in length from 2 '9 millims. in some to 2 '2 millims. in others, and even to 1'5 millims. 

 The stem spicules vary from 0'75 millim. to 2'3 millims. in length, but in one 

 specimen they reach 4'5 millims. in length. The polyp spicules also show considerable 

 variation, but it does not cover such a range as in the others. 



Some other specimens correspond more closely than the above do to previous 

 descriptions of this species. It appears to us that many of the species of Spongodes 

 are exceedingly variable, and we have therefore refrained from accentuating minor 

 differences. 



Locality : Cheval Paar ; pearl banks, Gulf of Manaar. 



SUB-FAMILY : SIPHONOGORGIN^. 



Paranephthya pratti, n. sp. Plate II., fig. 6 ; Plate V., fig. 18. 



A peculiar specimen with only the basal attachment missing was included in the 

 collection. We are indebted to Miss PRATT for a figure and the following notes. 



The colony, which is apparently young, is small and measures as follows : 



Height 21 millims. ; stalk 15 millims. 



Breadth of stalk, 13 millims. to 11 millims., of capitulum, 24 millims. to 20 millims. 



The capitulum is lobate, with deep grooves between the digitate lobes. 



The lobes (7 in number) are digitate and are comparatively large. The largest is 

 13 millims. in height by 7 millims. to 5 millims. in diameter. The smallest is 

 3 millims. in height by 5 millims. to 4 millims. in breadth. Some of the lobes are 

 beginning to branch dichotomously. 



The capitula are dotted with minute tubercles, and when observed under the 

 microscope have a curious polyzoon-like appearance. These tubercles indicate the 

 presence of the zooids which are small, degenerate in character, and are so overgrown 

 with minute spicules as to be only slightly contractile. They have apparently only 

 rudiments of tentacles. The mesenteries, are crowded with brown cells which are 



