418 PROF. J. A. THOMSON AND MR. W. D. HENDERSON ON [Apr. 10, 



thick coating of large spicules, either lying on, or proti'uding from, 

 the surface, many reaching a lengtli of 6 mm. 



On the capitulum, which is thin with incurved edges, the auto- 

 zooids appeal- usually in small groups of twos or threes. Each 

 group is genei'ally elevated on a small protuberance, or each auto- 

 zooid may have a slight elevation of its own. On the edge of the 

 capitulum the autozooids are moie numerous, and they do not 

 occur in gi^oups nor are they raised above the genei-al surface. 



The spicules are of two distinct types — (1) large spindles, either 

 straight oi' slightly curved, closely covered with small, rough, 

 wart-like projections ; and (2) small spicules which var}^ from 

 spindles to rods, with rough prominent projections, which often 

 cluster more closely at one end, thus giving a club-shaped 

 appearance. Theii- measurements are as follows : — 



(1) Length varies from l-4"6 mm. and the breadtli from 0"15- 

 0*55 mm. 



(2) Length varies from 01-0'5 mm. and breadth from 0-03- 

 0-075 mm. 



Locality. Wasin, 10 fathoms. 



ScLERorHYTUM POLYDACTYLUM Dana. (Plate XXXI. fig. 2.) 



A complete specimen 75"5 mm. in height. The lower part of 

 the stalk is very rigid, with spicules readily visil>le to the naked 

 eye. The upper part is marked by longitudinal grooves and folds, 

 and is devoid of the larger spicules which are present in the lower 

 part. 



The capitidum is divided into a large number of small, blunt, 

 finger-like lobes, on which the autozooids seem to be almost equally 

 distributed. 



The numerous small autozooids are almost all completely 

 retracted, a few can l^e seen with the tentacles appearing above 

 the surface. The tentacles are short (0"6 mm.) arid thick, with 

 the pinnules arianged in one row on either side of the middle line 

 of the oral surface. The eleven pairs of pinnules are small, cylin- 

 drical, and rather blunt. 



The spicules : 



I. Of the upper part of stem : — 



(a) Large straight or curved spindles covered with many rough 



tubercles, varying from 0-6-2'7 mm. in length and from 



O'l 5-0*5 mm. in breadth. 

 (h) Small straight or ii-regularly-shaped spicules with large rough 



spines, varying in length from 0"l-0*35 mm. and in width 



from 0-02-0-09 mm. 

 (c) Straight spicules with very few smooth spines, vaiying in 



length from 0'2-0"7 mm. and in width from 0"075-0'l 5 mm. 



They often show slight traces of four rays, and these show 



a X-marking at the junction of the rays. 



II. Of the lower part of the stalk : — 



The same types of spicules are present, but there is a mai'ked 

 predominance of («). They are more varied here and often show 



