32 Salt Marshes and their Inhabitants. 



found abundantly in both, fresh and brackish waters in the 

 counties of Somerset, Durham, and Northumberland.* When 

 it does occur it is generally in prodigious numbers ; a fact 

 accounted for by the unusually large number of ova which it 

 bears. The peculiar ringed and serrated hairs which occur on 

 the limbs of this genus and of Cythere' are very beautiful and 

 interesting objects for the microscope. 



Cyprideis has no power of swimming, its motions being 

 restricted to crawling ; but some of the natatory Entomostraca 

 are found in similar j)laces. These are chiefly of the same 

 family to which the common and well-known Cyclops guadri- 

 rornis belongs. The males of these animals have the right 

 antenna very strongly developed, and provided about the centre 

 with a hinge-joint, so that it can be flexed and used as a clasp- 

 ing organ. In some species, to render the apparatus still more 

 effectual, there is on each side of the hinge a plate armed with 

 spines or serratures, by which the grasp must be greatly 

 strengthened. The females may be seen toward the end of 

 summer and autumn, carrying about with them, attached to the 

 first segment of the abdomen, numbers of elongated cylindrical, 

 or fusiform bodies of a yellowish or deep red colour. These 

 are the " spermatic tubes," which have been fixed in that 

 situation by the male ; a curious mode of fecundation, which so 

 far as we know is peculiar to this family of Entomostraca. 



The highest, or stalk-eyed order of Crustacea, is represented 

 in brackish water by three species — Palcemon varians, My sis 

 vulgaris, and the common shrimp (Crangon vulgaris). The 

 last named is of almost universal occurrence, and calls for no 

 special remark here ; the other two species are comparatively 

 rare. The Palaemon is much smaller than its congener, P. 

 serratus (the common edible. prawn), and also quite deficient in 

 the beautifully variegated colouring which adorns that species. 

 Like the rest of its genus, it is very timid and very agile, so 

 that, except with a tolerably largo net, it is difficult to catch it 

 when in clear water. In muddy places the best way of getting 

 specimens is to force the net into the mud, so as to enclose a 

 considerable quantity; then on washing it a number of the 

 prawns will probably remain behind. It is curious that 

 although these creatures seem so much frightened at the sight 

 of a net, fchey will, if one's hand is put quickly into the water 

 and kept there for a minute or two, come boldly up to it, hover- 

 ing about, and Feeling it all over with their long antennee. A 

 crowd of them may lie thus eollertod in a very short time, but 

 Hie slightest movement makes them dart off rapidly, andlhave 

 always found it impossible to catch one in this way, even though 



* Tiilf ii paper by Hio present writer in Annals and Magazine of Natural 

 History, January, 18G1 ; also in Intellectual Ousekver, vol. i. p. 454. 



