Report on the Antipatharians. 77 



Mr Anderson's description, though a few of his data may- 

 be of service. 



Three of the five specimens were attached to small stones. 

 All were gracefully curved pinnate colonies, with the 

 branches nearly, but not quite, opposite, and not quite in 

 one plane. The lower branches make an acute angle with 

 those of the opposite side, but this angle increases with the 

 following branches till the two at the very top make a very 

 large obtuse angle with one another. 



In four of the specimens the total length of the stem 

 was found to be 18-5, 17, 16*5, and 16-5 cm. Three of the 

 four had ten branches on each side, while the longest 

 specimen had twelve branches on one side and thirteen on 

 the other. The branches occur in pairs with such strict 

 uniformity that one might suspect the loss of a branch. 

 But there is no hint of this. 



The branches on one specimen were measured, and the 

 lengths in centimetres from the base upward are given in 

 the following Table : — 



Right Side. Left Side. 



Branch. Length in cm. Length in cm. 



1 24 2-5 



2 Broken off. 2-5 



3 5-2 3-5 



4 6-8 4-7 



5 7-6 5-5 



6 7-6 6-0 



7 8-5 6-5 



8 7-5 6-5 



9 5-6 6-3 

 10 4'7 4-0 



Thus, on one side, branch 7 is longest, on the other 

 branches 7 and 8 are of equal length. The lower and higher 

 branches are shorter than the more central, and the grada- 

 tion of the graceful colony is on the whole regular. 



"Isolated" zooids occur both on the main stem and on 

 the branches; they are disposed on only one side of the 

 branches, at fairly regular intervals; their bases are con- 

 nected by coenenchymatous outgrowths. They correspond 



