31 



four to twelve imlividnals. They are placed at an angle which is usually 

 right, but may be obtuse, on fairly long stalks, which may measure up to 

 2'.i mm. in length, but which on an average are considerably shorter. The 

 groups on the lower part of the polyparium show a marked tendency to the 

 divaricate ty])e, but in the upper pait they stand more closely together. On 

 the edges and upper surface of the flattened lower bi-anches the polyps occur 

 singly or in small groups. The heads are rather large, being 0"9 nnii. high 

 and 0"65 mm. broad. The polyp-spicules are arranged in the following manner ; 

 the lower spicules, which measure from 0'33 to 051 mm. in length, are placed 

 horizontally, above them rise eight pairs of large spicules which run practically 

 parallel, being bent near the proximal end, the bent parts diverging ; one of 

 the pair is invariably larger than the other and projects further beyond the 

 polyp, the smaller being often replaced by two still smaller spicules. In the 

 spaces between adjacent pairs one or two small spicules are present, which in 

 certain stages of the polyp's contraction or expansion may be ])arallel to the 

 diverging parts of the large spicules. The latter measure from 0'48 to 0"9 mm. 

 in length and may project to half their length beyond the polyp-head. The 

 polyp-spicules are spindles, either straight or curved, and covered with regularly 

 arranged blunt spines or thorns. On the aboral surface of the tentacles there 

 are two rows of flattish toothed spicules, the ends of the spicules of the two 

 rows interlacing in an irregularly alternate manner. 



The Stutzbtindel is well developed, and contains several large spicules, one 

 of which may measure 2"5 mm. in length, and project for a distance of 11 mm. 

 Very frequently the tip of a second projects for a short distance. It is of 

 interest to note the different stages in the growth of the Stiitzbtindel, for in 

 many of the smaller polyps it seems to be absent. 



Cortical spicules : {ft) In the main stem and branches there are spindles, 

 straight or curved and covered with numerous blunt spines, regularly arranged. 

 They vary in length from 042 to 25 mm. and in breadth from 0072 to 018 mm. 

 In addition there is a corresponding series of flatter spicules, much smaller in 

 size and with fewer spines. In the principal stem and branches the spicules 

 are arranged so as to produce a granular appearance, which gives way to a 

 transverse stringy appearance only towards the tips, but in the smaller branches 

 there is a distinct irregular meshwork of spicules arranged obliquely and trans- 

 versely, and this continues up into the twigs. 



(h) The stalk contains thick spindles, rods, ovals, clubs, triangles, globular 

 and roughly four-sided forms, and a series of irregular spindle- to star-shapes. 

 All except the last series are covered with numerous rough or branched warts, 

 somewhat regularly arranged. The last series have equally prominent rough 

 warts, but fewer in number and less regularly arranged. Many of the spindles 

 are curved and show a greater development of warts on the convex side, and 



