ON THE SHETLAND CRUSTACEA, TUNICATA, ETC. 273 



The genus Cyrianassa is founded on the male of Iphinoe. The genus 

 is characterized (chiefly) by having the pereion very long, five segments 

 uncovered by carapace, and its posterior segments scarcely deeper than 

 those of pleon ; the last four pereiopods in both sexes without a palp ; 

 the telson rudimentary ; the uropods with both branches biarticulate, 

 the inner strongly spined: and in the male by having the first five seg- 

 ments of pleon furnished with well-developed biramous pleopods. I am 

 by no means certain that the present species is not the male, of Iphinoe 

 trispinosa. Undoubted males of that species resemble the I. gradlis 

 very closely, except that they have 2-3 spines on carapace, and the 

 pleopods have not the long plumose setae which adorn those of the latter 

 species. It is possible, however, that the development of these setae 

 may depend upon age, and that the presence or absence of the small 

 dorsal spines may not constitute more than varietal distinction. Puture 

 observation must be left to clear up this point. 



Cuma scorpioides, Bate, Ann. Nat. Hist. 2nd ser. vol. xvii. (1856) p. 456, 

 pi. xiv. fig. 2, = ? Cancer scorpioides, Montagu, Linn. Trans, vol. ix. 



Taken in Balta Sound in 1863. Known by its strong angular and 

 keeled carapace. Only four segments of pereion are exposed, and the 

 penultimate and the antepenultimate of these are raised into a rounded 

 rib across the back. The uropods have both branches two-jointed, and 

 only half as long as peduncle, subequal to each other, inner with nume- 

 rous short blunt spines, but the two distal ones of each joint long, outer 

 with plumose setae on the inner margin ; peduncle without spines or 

 setae, but minutely serrulate on inner margin. The male, as in Iphinoe, 

 has five well-developed pairs of pleopods. 



Order AMPHIPODA. 



Talitrus locusta (Linn.), 



Orclustia Uttorea. (Montagu). 



Probolium monoculoides (Montagu) = Mon tagua monoculoides, Bate & West- 

 wood. Bressay Sound, and 5-8 miles off Balta, 50 fathoms. Costa' s 

 genus Probolium (Eicerche sui Crostacei Amfipodi del regno di Napoli, 

 1853, p. 199) is synonymous with, and has precedence of, Bate's Mon- 

 tayua, which was established in 1855. 



marinum (Bate) = Montayua marina, Bate & Westwood. 5-8 miles 



east of Balta, 50 fathoms, and on the Skerries Outer Haaf, in 70-80 

 fathoms. 



Alderi (Bate) = Montayua Alderi, B. & "W. A single specimen of 



what I consider a variety of this species taken in Lerwick Bay. It dif- 

 fers from the ordinary form in having the hand of the second gnatho- 

 pods longer, being more than twice as long as broad, and in the palm 

 being less oblique, crenately toothed throughout (instead of in part 

 only), and the projecting tooth-like process bounding the palm of smaller 

 size. 



serratipes, n. sp. Antennae rather short. Second gnathopods with the 



metacarpus posteally produced into a small tooth-like process ; wrist 

 produced below into an elongated lobe, which stretches along the pos- 

 terior margin of the hand (after the manner of the genus Monoculodes) to 

 half its length, and terminates in two or three setae; hand of large 

 size, elongated, of somewhat unusual form, widest in the middle, from 

 which point the posterior margin gently slopes towards the anterior 



