116 



NOTES AND COKUESPONDENCE. 



On Mounting Polyzoa, and Kydroid Zoophytes, so as to dis- 

 play the outstretched Tentacles as in Life. — The g-reat beauty 

 of these preparationSj and I think I might add their un- 

 questionable value, render it desirable that as public an 

 answer as possible should be given to the numerous interro- 

 gations, as to the modus operandi, constantly received. 



So far as I myself am concerned, the discovery of the 

 process was nearly accidental, and originated in a half jocular 

 attack upon the ebriety of a very coy colony of Alcyonidice, 

 with spirit of wine, added drop by drop to the salt water 

 bath in which I had been watching their manoeuvres. To 

 my great delight I saw them come out one by one, and 

 slowly unfold their arms, till each Briareus among them was 

 as rigid and non-retractile as could be desired. 



The specimen upon which I made this first experiment is 

 in my cabinet still, as perfect as it was the day I rejoiced 

 over it at Longland Bay, near Swansea, in the summer of 

 1859. 



There is no need to spend many words in supplementing 

 so simple a matter. The principal points to be observed 

 are these : first, " catch your hare," of course, i. e., secure 

 vigorous and clean polypidoms. Next, mount them as soon 

 as you possibly can, or you will get but a flaccid and feeble 

 development ; some will not come out at all. I have gene- 

 rally found it necessary to have two or three baths of diflerent 

 fluids ready, and to assail those Avho may be proof against 

 one by the- potency of another ; Thwaites's fluid answers 

 admirably for most. In some cases a deposit of a mucilagi- 

 nous character takes place at the bottom of the cell ; it is 

 therefore well so to secure the covers as to admit of transfer 

 to a second cell, if necessary : hence a memorandum of the 

 original fluid, and its strength, should be kept. 



As a mere mechanical matter, it may be added that, when 

 practicable, it is a great security to cut the sea-weed or 

 polypidom of such length as to stretch the entire diameter 



