16 PROCEEDINGS OF Till: NATIONAL MUSEUM vol.69 



The largest specimen measures 13 mm. in length and differs from 

 Hansen's specimen measuring 14.5 mm. in the following points: 



(1) The presence of a very large and powerful spine on the lateral 

 margins of the carapace posterior to the center. 



(2) The median spine of the rostral plate is much more produced. 

 In the first of these points it agrees with the larvae described by 



Zimmer, which are, however, much smaller in size, measuring 5.5-10 

 mm. The lateral spine on the carapace is probably a larval character 

 but it is difficult to believe that the difference in size of this spine in 

 my own and Hansen's specimens can be explained entirely by the 

 small difference in total length. It rather suggests that the two 

 larvae belong to separate species. 



In the second of the above points my larvae differ from those de- 

 scribed by both Hansen and Zimmer, which are in substantial 

 agreement in the form of the rostral plate. The figures which 

 accompany this report will bring out the extent of this difference and 

 it is only necessary to add that the rostral plate is of very much the 

 same form in the smallest as well as the largest specimen. 



I can not see any trace of ripple markings on the carapace such as 

 are described and figured by Zimmer in his larvae and my specimens 

 show a further point of difference in that there is no long spine on the 

 dorso-lateral angle of the last abdominal somite, but the epimeral 

 plate is acutely pointed at the postero-lateral angle. In other 

 respects, allowing, of course, for the different degree of development 

 of the appendages due to differing age, my specimens agree fairly 

 well with those of Hansen and Zimmer. Particularly characteristic 

 of my specimens is the clumsy external form and the unjoin ted 

 narrowly conical flagella of the antennules and antennae. All the 

 specimens are from very deep water. 



Genus MEGANYCTIPHANES Holt and Tattersall 



18. MEGANYCTIPHANES NOKVEGICA (M. Sars) 



Occurrence. — Station 10158, 600-0 m., 1 specimen; station 10160, 

 100-0 m., 12 specimens. 



Remarlcs. — The two stations at which this species occurred are 

 in the coastal region, 10160 in purely coastal waters, 10158 in the 

 region of mixture between coastal and Gulf Stream water. The 

 fact that M. norvegica occurred only at these two stations confirms 

 what was previously known of its distribution on the Atlantic coasts 

 of America, where it is conclusively a coastal and not an oceanic 

 Gulf Stream form. 



