it 



MR. G. S. BRADY'S MONOGRAPH OF 



few -mall round papillae. Colour white. "Antennae and limbs similar to those of 



0. latMmum." 



Length tA, in. 



/////;. Galway Bay, off the Isles of Arran, in 10 fathoms water (G. S. B.). 



Like Sars, I at first took this to be the young of the following species; but a minute 

 \ animation shows decided specific differences, which will be best appreciated by exami- 

 nation of the figures. One specimen only occurred in my dredgings. 



2. Cythtkopteron latissimtjm (Norman). (Plate XXXIV. figs. 26-30.) 



Norman. Nat 



Brady, 



Trans 



Cytheropteron convexum, G. O. Sars, loc. cit. p. 80. 



British type. Distribution : Recent — Baffin's Bay, Norway, Great Britain, Ireland. Fossil — Glacial, 

 Scotland, Norway. 



Lateral protuberance moderately prominent, obtusely angular behind. Carapace of 



the female, seen from the side, obliquely subovate, greatest height in the middle, and 



equal to considerably more than half the length ; anterior extremity narrowed, rounded ; 



posterior produced in the middle into an obtusely rounded angle. Superior margin 



arched ; inferior convex, slightly sinuated in front of the middle. Outline, as seen from 



above, subovate, angular behind the middle, thence suddenly tapering to the posterior 



extremity, which is sharply pointed ; greatest width equal to more than half the length. 



Ventral surface flat, often longitudinally striated. End view triangular, equilateral, base 



fiat, sides convex. Shell of the male more elongated. Colour white. Surface of the 



valves marked more or less distinctly with oblong, slightly curved pittings, running in 



transverse rows across the shell. "Second joint of the upper antennae about equal in 



length to the fourth, the last very short. Second joint of the last pair of feet much 



longer than the two following. Distal portion of the male copulative organs obtusely 



truncated at the apex, the trifurcate spine narrow and shorter than the rest." 

 Length -4^ in. 



Hah. In depths of from 10-80 fathoms. Shetland (Mr. J. G. Jeffreys) ; Aberdeenshire (Mr. Dawson) ; 



Loch Fyne (Rev. A. M. Norman) ; Oban, Bute, Cumbrae, Macduff, Peterhead, and Ormeshead 

 {Mr. D. Robertson) ; Northumberland, Durham, and Yorkshire coasts (G. S. B) ; Norfolk coast 

 (Mr. D. O. Drewett) ; in shell-sand from the River Ribble and Isle of Wight (Mr. E. C. Davison). 



A very pretty and well-marked species, distinguishable from the following (C. nodosum) 

 by the less angular outline and the absence of any well-defined transverse ribs and nodes 



as well as by its larger size,— from C. punctatum also by its much greater size, less 



pronounced lateral alae, and the character of the surface-marking It has been wrongly 



identified by G. O. Sars with Cythere convexa, Baird, a totally different species, which 

 has not yet been noticed on the Norwegian coast. 



o 



34, 



3. Cytheropteron nodosum, n. sp. (Plate XXXIV. figs. 31- 



Atlantictype? Distribution: Recent- Britain, Ireland. Fo^7-( i lacial , Scotland, Ireland. 



Similar to the preceding, but much smaller. Carapace of the female, as seen from the 



