92 



1-12 mm. long, from O'll to 0'16 mm. broad, with few simple spines on the 

 surface ; smooth, Hat, striated rods ; and three-rayed forms with a few blunt 

 teeth on the edges. 



(//) In the stalk there are spindles with a few spines and a very large 

 number of smooth, flat, striated forms, with blunt teeth on the edges. Measure- 

 ments are on an average about the .same as in stem canal walls. 



Colour — Stalk, stem and branches creamy-white ; polyp-stalks, in their 

 lower portions, speckled with red, in their upper portions slightly deeper red; 

 polyp-spicules for the most part deep red, a few colourless ; polyps semi- 

 transparent to white. 



Locality : Andamans. 



Dendronephthya pellucida, Henderson. 



The colony is almost complete, wanting only a few branches ; it measures 

 5-6 cm. in height and 41 cm. in maximum breadth. 



The short stalk is flabby, somewhat damaged, 

 granular in appearance and about 1 cm. long. 



The polyi)arium is oval in outline and greatly 

 flattened in one jjlane. It consists of a large num- 

 ber of branches which increase in size towards the 

 upper part of the polyparium. The arrangement 

 of spicules on the stem is very characteristic, pro- 

 ducing a peculiar network appearance ; this arrange- 

 ment disappears in the branches, where the spicules 

 tend to run parallel to the length of the branch. 



The polyps are arranged in small groups of three 

 to thirteen, but five to nine are the common num- 

 bers. The groups are arranged in larger groups in 

 which all the polyps are so placed that they reach the surface of the polyparium. 

 The surface of the larger groups is almost flat. The heads are low and oval, 

 measuring on an average 0'48 mm. high and 0'56 mm. broad. They are placed 

 at an obtuse angle on short stalks of about 0"5 mm. The spicules are arranged 

 in the following manner : There are eight double rows in each of which there 

 are four to five pairs of converging spicules which are colourless and meet at an 

 acute angle ; below the lateral double rows a number of red spicules may run 

 parallel to the base of the polyp. The polyp-sjDicules average 024 mm. in 

 length. 



The Stiitzbiiudel is only moderately developed, and consists of a number of 

 spicules which average about 1"6 mm. in length in the largest. One or two of 

 them may project for a short distance beyond the polyp. 



Fig. 46. D. pellucida. 



