304 BRITISH ENTOMOSTRACA. 



plunge themselves deeply amongst the filaments of which 

 these organs are composed, and remain so firmly fixed to 

 the spot where they attach themselves, that iro efforts can 

 make them move. " They allowed themselves," says 

 M. Edwards, " to be torn to pieces, without making the 

 least movement, or quitting their hold. Plunged into 

 fresh-distilled water they were soon killed, but did not 

 fall off, and when the piece of gill putrefied, they putrefied 

 along with it, without their ever making any motion. 

 When plunged into spirits of wine, they made no move- 

 ment of contraction visible, even when examined by means 

 of the microscope. Taken carefully off, with all possible 

 precautions not to injure the animals, and placed in a 

 glass of sea-water, though watched for several hours, and 

 though they lived during that period, as might be seen 

 from the peristaltic movement of the intestine, they made 

 no attempts themselves at locomotion." 



The males have never yet been observed, but in all 

 probability, as the animals of this genus approach so 

 much in their habits to those of the Lerneadse, they are, 

 as in them, very small, unattached, and capable of moving 

 freely about in the gill-cavity, or attaching themselves to 

 the females. 



All the specimens yet observed have had the wing- 

 shaped appendages, and invariably, when of a large size, 

 have had the external ovaries suspended from the body, 

 and full of eggs. These are spherical in shape, and of a 

 very pretty rose colour. After the egg has made some 

 progress, it assumes the appearance of a somewhat irre- 

 gular oval, a little flattened on its sides, on each of which 

 a pair of limb-like knobs or excrescences are visible, 

 situated at a little distance from each other. The front 

 pair most probably become antennae, and the posterior, 

 foot-jaws. 



A very curious circumstance has been observed by 

 Rathke, with regard to the further development of these 



* Ann. So. Nat., ix. 



