30 W. M. TATTEESALL. 



The absence of median setse from the apex of the telson is not necessarily 

 of generic importance, since the genera Pseudomtna and Dactylerythrops both contain 

 species in some of which these setae are present, and others in which they are 

 wanting. As, however, all three species at present referred to this genus are without 

 median apical setse, it is convenient to retain this character in the generic definition. 



DaCTYLAMBLYOPS HODGSONl. 



(PL VI., Figs. 9-16.) 



Dactylaniblyops hodgsoni, Holt and Tattersall, ]906 (1). , 



Dactylerythrops arcuata, lUig, 1906. 



Locality of capture :—Lat. 66° 52' 09" S., long. 178° 08' 15" R, 2030 fathoms, 

 one specimen, male, 13 mm. 



The single specimen in the collection is considerably damaged, the antennules, 

 antennal scales, and the third to the eighth thoracic limbs being missing. A complete 

 description is therefore not possible, but it is hoped that as many of the characters as can 

 be made out with certainty will suffice for future recognition of the species in collections. 



Carapace submembranaceous, covering all the thoracic segments except the last 

 one, anterior margin produced into a blunt, broadly but evenly rounded rostrum 

 projecting between the eyes ; cervical sulcus well marked ; antero-lateral angles rounded. 



Pleon slightly longer than the carapace ; first five segments subequal in length ; 

 sixth nearly twice as long as the fifth. 



Eyes (Fig. 9) small, placed on definite peduncles, not in any way contiguous, 

 pyriform in shape, external angle evenly rounded, a short digitate process arising from 

 the inner dorsal face ; visual elements imperfectly developed, apparently represented 

 by numerous minute granular bodies with a refractive centre ; a large opaque ganglionic 

 mass, probably the optic nerve, visible in the peduncle,, from which a nerve fibre 

 proceeds to the cornea. 



Antennal peduncle short, composed of three subequal quadrangular joints. 



Antennal scale broken on both sides, but there does not appear to be a spine on 

 the outer corner of the basal joint. 



Mouth parts (Figs. 10-13) not differing markedly from those figured by Sars for 

 Amhlyops abhreviata (1870-79). 



First thoracic limbs (Fig. 14) with the endopod substantially of the same form as 

 in A. abhreviata. 



Second thoracic limbs (Fig. 15) of essentially the same structure as in A. abhreviata, 

 but with the endopod apparently much longer, being nearly twice as long as the 

 endopod of the first thoracic limbs. 



Genital appendix to the last thoracic limbs of the male terminating in two lobes, 

 the larger of which bears six long setse, the smaller one being devoid of setse, but 

 apparently having a covering of very fine hairs. 



