VIRGULARIA. 185 



I am indebted to the skill of two distinguished chemists for an ana- 

 lysis of this singular organization, Dr Andrew Fyffe, Professor of Chemis- 

 try in the University of Aberdeen, whose residence in Edinburgh was long 

 of eminent service to various departments of the arts. Further, to Dr 

 David Boswell Reid, whose zeal and activity in promoting science in the 

 same city, have left a blank, not to be easily filled up, by his removal to 

 the metropolis. 



From a quantity of the bone with which I supplied Dr Fyffe, he 

 found it to consist of 85 parts of carbonate of lime, and 15 of animal mat- 

 ter, blended throughout with the former. In like manner, Dr Reid found, 

 from a quantity with which I supplied him, the principal ingredients to be 

 phosphate of lime, carbonate of lime, and animal matter; the latter in 

 considerably quantity, " leaving, when the earthy matter was dissolved in 

 acid, a pulpy jelly." On the whole, he was disposed to consider the sub- 

 stance more as bone than shell, though different from any bone or shell he 

 had previously met with. 



I question whether the Virgularia has any proper locomotive faculty 

 whatever ; whether it can really shift its place by its own exertions. If 

 so, it may be from some inducement, and by some means, which are not 

 obvious. The parts move very little in confinement ; yet the body can 

 twist itself, if it may be so described, in such a manner as to form a spiral 

 around the bone. A section, six or eight inches long, standing inclined 

 in a narrow jar, will be found to have arranged itself in a single volute 

 throughout, or into two, three, or four, between night and morning. The 

 whole can relax again into a straight line by their obliteration. But when 

 laid horizontally in a wide vessel, I have not observed any specimen turn 

 itself over, whether the position of the edge of the lobes bearing the hydra? 

 be upwards or downwards; that is, whether the Virgularia lies on what 

 may be called the back, or on the front. 



The lobes have an independent power over their own position, assum- 

 ing greater or less obliquity, and closing by reciprocal approximation. They 

 exhibit nothing more. The aspect of the hydras is more delicate than 

 that of the others ; they have all the motions peculiar to those of the as- 

 teroid zoophytes. 



VOL. II. 2 A 



