

38 Prof. E. Kay Lankester on Hamingia arctica. 



two specimens of Hamingia 7 placed in his hands by the 

 committee of the u Barents " Dutch Arctic expedition, which 

 were obtained in veiy nearly the same latitude as that described 

 hj Koren and Danielssen. Dr. Horst was able to add some 

 particulars as to the vascular system and alimentary canal to 

 the very precise and full account of the anatomy given by 

 Koren and Danielssen. He has, however, without assigning 

 any definite reasons, given to his specimens a new specific 

 name u glacialisP There is, it seems to me, no ground for 

 supposing that Dr. Horst's specimens belong to a new species* 

 The summary of characters given by Koren and Danielssen 

 is as follows. It mast be remembered that the conclusions 

 of the Norwegian zoologists are derived from the study of a 

 single specimen preserved in spirit. 



Generic Characters. 



u Body cylindrical ; mouth at the anterior extremity nearest 

 the ventral surface. Anal opening in the centre of the poste- 

 rior extremity. A lunate somewhat prominent fold round 

 the mouth (rudimentary proboscis). On the anterior portion 

 of the ventral surface two long, cylindrical papillae, having 

 each at the apex a round aperture for the efferent duct of the 

 corresponding uterus. No bristles* 



u The intestinal canal with numerous circumvolutions, but 

 no spiral coil ; it disembogues into a cloaca, from both sides 

 of which issues a ramifying glandular apparatus. 



u The central nervous chord smooth, destitute of nodes or 

 ganglions. 



u One ovary protruding along the nervous chord in the pos- 

 terior half of the perivisceral cavity. 



u Two uteri, each with an efferent duct and funnel-shaped 

 tube . 



u The male as yet unobserved." 



Specific Characters. 



u Body cylindrical, smooth, 120 millim. long, 20 millim. 

 thick, repeatedly changing its form as it contracts and expands. 

 Colour a lighter or darker grassy green. Buccal disk whitish 

 yellow ; the arcuate papillae on the ventral surface greenish 

 with whitish yellow extremities/' 



Occurrence of new Specimens. — In the month of August of 

 this year (1882), which I spent in dredging at Lervik, at the 



m 



outh of the Hardanerer 



Mr. A. G. Bourne, a specimen of He 



gia arctica was brought up in the dredge. The specimen was 

 dredged on a rocky bottom, at about 40 fathoms depth, just 



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