54 



HYDROIDA II 



side. The apophyses have each an imbranehed hydrocladium , divided by transverse joints into 

 segments with numerous hydrothecae. Each, or more rarely, every alternate internodium on the 

 hydrocladium has on its distal half a hydrotheea entirely fused down its one side with the inter- 

 nodium, or more rarely having a low free adcauline edge. The hydrotheca-bearing internodia are also 

 distally furnished with a median pore, proximally with a median pore having raised edges, through 

 which the naked sarcostyles pass. The length of the hydrotheea varies between l ■', and ' s of that 

 of the internodium. 



The gonothecse are situated on the stem or on the basal parts of the hydroeladia, without 



2°° m - boom ._ 1000m. zooom. 



Fig. XXIII. The distribution of Kirchenpaueria pinnata in the Northern Atlantic. 

 In the hatched regions a common occurrence is stated by the literature. 



special protective organs. They are oval to pear-shaped, smooth or spiny, often much flattened from 

 the side. 



Forma typica. Short internodia with hydrotheea; in length from '/, to ' ., the internodium. 



Forma elegantula (G. O. Sars) slender internodia with small hydrothecae, length as a rule from 

 1 I S to '/s of the internodium. 



Material (forma typica): 



Greenland? (without further details). 



The Faroe Islands: (without further details) |= Plu miliaria echinulata Winther]. 



The synonymy of the species has recently been worked out by Bedot(io,i.6). It gives us an 

 interesting insight into the variability of a species, and throws a sharp light upon several of the 



