Rev. Canon A. M. Norman on British MysMiu. 253 



cleft to about one fifth of its entire length, the cleft very 

 narrow and constricted at the base ; margins of telson with 

 eighteen to twenty spines. Inner uropods spined almost as 

 in the last, but the otolith is proportionately smaller. Length 

 about 20 millim. 



IJah. Jersey ; Guernsey ; Starcross, Devon ; Plymouth 

 {A. M. N.) ; mouth of Loch Fyne [Dr, Henderson) : Mus. 

 Is or. North Wales [A. 0. Walker). 



Distribution. Hardanger Fiord, Norway [A. M. N.) ; South 

 and West Norway and Lofoten Islands {G. 0. Sars) ; Den- 

 mark [Me inert). 



3. Macromysis inermis (Rathke). 



1848. My sis iiiernu's, Rathke, Beitrjige zur Fauna Norwegens, p. 20. 

 1852, Ml/sis inermis, liilljeborg, (Efvers. af Vet.-Akad. Forhand. p. 3. 

 18G1. Mysis cornitta, Kroyer, Nat. Tidsskr. ^^^ Ra^kke, vol. i. p. 20, 

 pi. i. figs. 3a-ff. 



1863. Mysis cornuta, Goes, Crust, dccap. podoph. marina Suecife, 

 p. 14. 



1864. Mysis triincatula, G, 0. Sars, Beret, om en i Somm. 1863 fore- 

 tagen Zoolog. Reise, p. 10 (monstrositas). 



1869. Mysis inermis, Norman, " Last liepovt Dredging Shetland Isles,'' 



Brit. Assoc. Eep. for 1868, p. 206. 

 1879. Mysis inermis, G. O. Sars, Carcinol. Bidrag til Norges Fauna, 



I. Monogr. Mysider, p. 54, pi. xxvii. 

 1882. Keslerella cor^mta, Czeruiavsky, I. c. fasc. ii. p. 36. 



1882. Keslerella similis, Czemiavsky, I. c. fasc. ii. p. 38. 



1883. Keslerella cornuta, similis, inermis, tnmcatula, and Go'esi, Czemi- 

 avsky, /. c. fasc. iii. pp. 67-71. 



Anterior margin of cephalothorax not produced, widely 

 rounded, and exposing in front of it a sharp triangular spine 

 which springs from between the bases of the antennules ; 

 while thus the margin is not rostrately produced as in the 

 last two species, this spine gives the appearance of a ros- 

 trum. Antenna! scale half as long again as the peduncles 

 of antennules and about four times as long as broad; apex 

 ])roduced beyond base of spine of outer margin to two or three 

 times the length of that spine. Tarsus of legs consisting 

 of four articulations ; nail well developed and stronger than 

 in allies. Telson cleft to nearly one third of total length, 

 cleft very narrow ; margins of telson with about seventeen 

 spines. Inner uropods having few marginal spines, only 

 about six, which, as in the preceding species, gradually 

 increase in size distally. Length about 20 millim. 



Hah. Rock-pools, Shetland ; Cullcrcoats, Northumber- 

 land; Oban; Plymouth; Guernsey [A. M. N.) ; BanfF [T. 

 Edward); Tarbert, Loch Fyne (Thomas Scott) : Mus. Nor. 

 Firlh of Forth (T. Scott) ; Isle of Cunibrae((/. Ii. Henderson). 



