2, i, 2, i, fossa, 2, 2, 2; the marginal spines on each side: 6 — 3 — 7. The sublateral carina 

 on the branchial region carries on either side 5 spines ; just as in Smith's figure (1. c. 1882, 

 PI. III) the distances between these spines somewhat increase from before backwards and the 

 posterior one is just twice as far distant from the fourth as the first from the second. This 

 sublateral carina, though nearly parallel with the lateral margin of the carapace, appears, indeed, 

 very slightly curved, so that its distance from the lateral margin is somewhat larger in the 

 middle than at its extremities. 



The tooth or spine in the middle of the anterior border of the ophthalmic lobe is small, 

 sharp, directed outward and as distinctly developed as in the variety pacijïca ; according to 

 Alcock, this spine should be wanting in the specimens from the Arabian Sea. The 5 lh legs 

 are subcheliform ; the immobile finger is obtusely pointed, the dactylus, twice as long, tapers to 

 a sharp extremity and is slightly incurved. 



The other example agrees with that which has been described. 



Measurements in millimeters: 



Length from front of carapace to tip of telson : 



Length of carapace along inedian line : 



Width of carapace between the tips of the spines at the antero-lateral angles: 



Greatest width, in front of cervical suture: 



Length of i st pair of legs: 



„ merus of these legs: 



„ carpus „ „ „ 



n » cnela „ „ „ 



„ „ dactylus of „ „ 



Greatest breadth of abdomen at the second somite: 



„ sixth somite : . 



Length of telson : 



C? 



94 

 4i 

 20V4 



31V2 



Width of telson ; 



25 

 8V, 



cT 



47 

 21 



9 



I4'/ï 



52 



I5V» 

 8 



i6'/ 2 

 9'A 



n »/ a 



6 



Stereomastis auriculaia (Sp. Bate) from Kandavu Island is, no doubt, different. The median 

 line of the carapace, between the two rostral teeth and the cervical suture, carries two single 

 teeth more, the sublateral carinae on the branchial region are more strongly waved and armed 

 with a larger number of teeth, the inner and the outer margin of the orbital notch are nearly 

 parallel with one another and with the median line of the carapace and the 5 th abdominal 

 tergum carries "no tooth, but a small, carina-like ridge". 



A closely allied form is also Polycheles Tanneri Fax., which, besides by its more or 

 less developed epipods on the thoracic legs, may easily be distinguished by the different armature 

 of the lateral margins and of the upper surface of the carapace. Pol. Tanneri forms, however, 

 just in virtue of the spinulation of its carapace and of the feeble development of its epipods, a 

 remarkable transition from the genus Polycheles to the genus Stereomastis (vide p. 22). 



Geographical distri bution: Southeast of Sable Island, off the coast of Nova 

 Scotia, 250 fathoms, also at other localities off the East coast of the United States, e. g. off 

 the mouth of Chesapeake Bay, at depths varying between 300 and 843 fathoms (S. I. Smith); 



S1BOGA-EXPEDITIE XXXIX a- 



