i6o DISCOVERY REPORTS 



The cirrus sockets are arranged in about fifteen irregular columns ; the columns are 

 least regular near the ventral edge of the centrodorsal, around which there are about 

 twenty sockets. 



Cirri about XXXV, 25-30. The distal segments, from about the tenth outwards, have 

 a rounded dorsal keel which is not shown in Carpenter's figure ; it is stronger than that 

 of E. fraseri. 



Pi is long, stiff and slender, of 12 evenly tapering segments, 4-5 mm. long. The first 

 two segments are heavy and broader than long; the third and fourth are about as long 

 as broad ; the remainder are elongated and become more and more slender to the tip of 

 the pinnule. The distal edges are thorny. 



P2 , of 1 1 segments and about 4 mm. long, is similar. Carpenter describes it as carrying 

 a gonad: if it is a gonad, it is very small. 



The remaining pinnules arise from regenerated brachials and do not bear gonads. 



Eumorphometra concinna A. H. Clark 

 A. H. Clark, 1915 a, p. 118, pi. ii, figs. 2 and 3. 



This species is known from the five specimens taken by the Deutsche Siidpolar 

 Expedition in 380-400 m. off Gaussberg in the Indian Ocean sector of the Antarctic. 

 It has not been recorded since. Upon re-examining a female co-type Mr Clark found 

 that there were brood-pouches alongside the ovaries. Knowing of the number of brood- 

 protecting species that I had among the Discovery collection, he immediately sent me 

 a portion of the arm and a number of detached pinnules with permission to describe 



them here. 



The arm fragment is from the middle of an arm and carries a few of the distal 

 genital pinnules and the first of the outer pinnules. The distal edges of the brachials are 

 raised into stronger spines than those of the corresponding brachials in E. aurora. 

 Along the pinnule ambulacra there are reduced rod-like side- and cover-plates like 

 those of E. aurora, except that some are strongly thorny. 



The brood-pouches lie on the aboral side of the pinnules, nearest the arm. The walls 

 are so thin that the contents of the pouch can be seen through them. The eggs in the 

 ovaries and the embryos in the brood-pouches are of different sizes and at various stages 

 of development. The biggest eggs are oval and as much as o-2-o-25 mm. long. The 

 biggest of the brood-pouches contains 13 embryos. Seven are without trace of skeletal 

 plates or ciliated bands; they are spherical or irregularly oval, o-2i-o-2g mm. Six are 

 oval embryos with the beginnings of skeletal plates within them. One is smaller than 

 the others, 0-34 mm. long, and with no ciliated bands. There are about 14 small stem- 

 plates and a very large terminal plate, and there are five orals and five basals but no 

 infrabasals. Three other embryos in good condition are slightly bigger, o-37-o-40 mm. 

 long and o-29-o-36 mm. wide, and possess ciliated bands. They have about 18 stem- 

 plates. In two of them there are two very small infrabasal plates— I cannot see a third 

 in either of them or any infrabasal plates in the third embryo. The three posterior bands 



