SALT-WATER POND AT AMBLE. 333 



characters of the first pair of footjaws. The present species 

 may be easily recognized by a conspicuous dusky patch at 

 the base of the anterior antennae (fig. 2). It occurred in con- 

 siderable numbers in the netting from the deeper water of the 

 pond. This is the first record of its occurrence in our district, 

 and it has been found by the Messrs. Scott only in two 

 localities — Firth of Forth, and Hilbre Island, Liverpool Bay. 



Genus ECTINOSOMA, Boeck. 



Ectinosoma brunnea, sp. nov. (Plate 9, figs. 4-1 1). 



The body is rather stout (fig. 4), and usually without flexure 

 at the junction of thorax and abdomen : it is rather larger 

 than most species of the genus, but otherwise there is not 

 much that is distinctive in its general build except that the 

 colour is usually of a dark brown. Anterior antennae (fig. 5) 

 short and stout, five-jointed, and densely setiferous ; posterior 

 antennae (fig. 6) much larger than the anterior, the secondary 

 branch three-jointed, reaching at least as far as the apex of 

 the main branch, the median joint very small, last joint very 

 long and slender; anterior footjaws (fig. 8) very stout, the 

 two joints equal in size and about as broad as long ; posterior 

 footjaws (fig. 9) slender, three-jointed, last joint about half as 

 long as the two preceding joints, the first two joints bearing a 

 few marginal setae— three apical setae, the middle one much the 

 longest. The basal joint of the fifth foot (fig. 10) is prolonged 

 internally, forming an oblong subquadrate lamina somewhat 

 furcate at its extremity, tipped with two stout plumose setae, 

 and bearing on its inner margin a few spine-like hairs : the 

 outer segment of the basal joint ends as usual in a single 

 seta : the second or distal joint is divided into three digitiform 

 lobes of nearly equal length, each bearing an apical plumose 

 seta, that of the middle lobe being much the longest; the 

 innermost digit has also two additional but very short setae. 

 Furca of moderate length, about twice as long as broad 

 (fig. 11), bearing three apical setae of unequal length. Length 

 of the animal, exclusive of tail setae, "85 mm. 



