496 



MR. JAMES RITCHIE ON HYDROIDS 



[May 28, 



proboscis and short (0"3 mm.) stumpy tentacles. These, between 

 40 and 50 in number, are scattered over the body of the polyp, 

 only the distal 4 or 5 being placed in a whorl, although an 

 approximation to whorling is sometimes simulated by others of 

 the tentacles. At the proximal end of the hydranth there is a 

 short neck, and just within the margin of the tube a sharp bulge 

 connecting the polyp with the coenosarc of the ramulus and almost 



Text-fig. 142. 



X.-P 



Solenio^sis dendriformis. To show mode of branching, X 8. 



ooeM., ccenosarc; feri., perisarc; hr., branch bending off and becoming free from 

 main stem; st., main stem; ram. 1, 2, 3, short ramuli from which hydranths 

 project; n.t. 1, 2, 3, 4, new tubes, enveloping a branch from a coenosarcal 

 strand and wedged in between older tubes. 



plugging up the entrance to the tube. Contracted, the hydranths 

 form almost spherical bulbs about 0*7 mm. in diameter. Although 

 the tube from which the hydranth springs generally ends abruptly 

 with an even circular margin, in not a few cases the terminal 



