1G8 (/anon A. i\r. Norman on a 



two move s])Pcies to the rrenns — IT. aJt/in'cus, from Alo;erin, 

 and Il.provinciaJis, from Golfe de Saint-Tropez. The species 

 now to be described comes nearest to //. Orstedi. 



Tlefprotnnain Gurneyu sp. n. 

 (PI. V. figs. 1-7; PI." VI. fig. 1.) 



Heferotatiais sp. (?), Robert Giirnej^ " The Fresh- and Braclvisli-AVator 

 Cnisitaoea of ]"]ast Norfolk," Trans. Norfolk and Norwich Naturalists' 

 Soc. vol. vii. 1904, p. G50. 



Mr. Robert Gurney, in his excellent paper on the fauna of 

 the Broads &c. of Norfolk, indicated as above a Tanaid which 

 he had found in brackish water. He was subsequently so 

 kind as to send me a male specimen and also drawings of the 

 female, with a request that I would describe tlie species ; 

 from that specimen and tlie drawings tlie following characters 

 are given. 



The length of the female is equal to about five times that 

 of the breadth, and the breadth is nearly equal throughout. 

 The cephalosome is as long as the first three segments of the 

 mesosome and half of the fourth; the fourth and fifth seg- 

 ments of the mesosomo are tlie longest ; and tlie metasome 

 equals the two and a half preceding segments in length. The 

 antennules are three-jointed, the first exceeding in length the 

 two distal joints combined. The cheliped is almost exactly 

 like that of II. Orstedi, the thumb having three crenations 

 and as many setae. The second pair of legs have the 

 characteristic formation usual in the genus. 



The male has the cephalosome produced and very com- 

 i)ressed, narrowed greatly in front to the region of the eyes. 

 'I'he metasome is fully equal in lengtii lo half the mesosome. 

 The antennules consist of five articulations, of which the 

 terminal is the shortest, and the second nearly equals the 

 combined lengths of the last three. Tlie cheliped in general 

 structure resembles that of //. Orstedi, but as seen from the 

 outside the carpus is not projected so far forwards, while the 

 thumb-process is of entirely different form, (not narrowed at the 

 base, and thence widening, but) narrow throughout its length 

 and of subequal breadth, until near its termination it is bent 

 forwards, and pointed at the extremity. The uropods have 

 the outer branch minute, two jointed; the inner four-jointed, 

 the two distal joints being subequal to the second in length. 



This species very nearly resembles //. Orstedi in most 



1 



