ZOOPHYTES. 249 



such that it cannot sustain itself unsupported ; whence, it either hangs as 

 a parasite from other marine substances, or stretches along the surface of 

 shells. 



The stem, no thicker than a human hair, extends sometimes an inch 

 and a half in length. It is smooth and tubular, seldom with any branches ; 

 though specimens do occur with several, and then they diverge to right 

 and left. 



Numerous clusters of from six to eight or ten ovate cells are im- 

 planted on the stem and branches, at intervals, and occasionally with con- 

 siderable regularity. The cells may be also seen in pairs, when one cell is 

 on each side of the stem. Here the clusters are more numerous, and in 

 nearer approximation to each other, than in the species above described. 



An ascidian hydra, with eight cUiated tentacula, occupies the cell, 

 which, like the other, is prolonged on its protrusion. 



This zoophyte is commonly of dingy white or greyish colour. 



The specimen represented did not exceed half an inch in length. 



Plate LI. Fig. 1. Valkeria cmcuta, magnified. 

 2. Hydra magnified. 



The reader will find some interesting remarks by Dr Fleming, in the 

 Memoirs of the Wernerian Society, vol. iv. p. 485, PI. xv. 



J 3. Valkeeia lendigera — Nit Coralline. — Plate LII. — The name 

 Syrinoc or Paris Pipe, would have been more characteristic than any 

 hitherto given to this zoophyte, from the intimate resemblance of some of 

 its parts to that instrument, — presuming the species now described to be 

 identified with that of preceding naturalists. 



I am aware that it is proposed to institute a new genus Serialaria, 

 which shall include the species before us. But as this seems to have been 

 done in ignorance of the nature of the hydra belonging to it, and the ge- 

 neral features being common to what the Valkeria may comprehend, per- 

 haps its true place is very near to this section, and may be included here. 



VOL. I. 2 I 



