12 A 



Canadian Arctic Expedition, 1913-18 

 Henlea ochracea (Eisen.) 



A collection made July 26, 1916, at cape Bathurst, Northwest Territories, 

 from a " water-hole in brook swamp (tundra) " contained two mature enchy- 

 traeids which exhibit characters very similar to those described by Eisen 

 (1879 : 20) for Henlea ochracea. Eisen's description is so meager that other 

 workers have had difficulty in using it. The writer, in a careful examination 

 of the original description and its accompanying figures, has found so <!<>' 

 an agreement with the Canadian specimens that they are listed here as Henlea 

 ochracea, at least provisionally. 



CHARACTERISTICS. Length, 12 mm. Maximum diameter, .0-7-1 mm. 

 Somites, 47. Colour of alcoholic specimens dark brown. Prostomium prom- 

 inent; smooth; rounded at tip; extending well beyond mouth. Setae straight : 

 inner ones of bundle slightly smaller than outer; 3-5 per bundle, fewer at 

 extremities. Clitellum on 12-13; well developed; continuous around body. 

 Lymphocytes sparse; ovoid to circular. Brain almost as long as wide; anterior 

 margin slightly concave; posterior margin emarginate; lateral margins divergent 

 caudad; almost circular in transverse section. Two sets of peptonephridia 

 arising from digestive tract in 5; dorsal pair arising as large, tubular, glandular 

 organs, extending caudad for short distance between epithelium and muscle- 

 layer of alimentary canal, ending in a few long branches into coelom in 6; ventral 

 pair arising as two tubular strands, more massive than dorsal peptonephridia, 

 also few branches into coelom in 6. Oesophagus expanding abruptly into 

 intestine in 8. Intestinal diverticulum in 8; completely surrounding digestive 

 tract as single organ; with numerous internal tubules. Origin of dorsal blood- 

 vessel in 9; vessel exceptionally enlarged above diverticulum. Nephridia with 

 very small anteseptal and large postseptal part; efferent duct arising from 

 posterior end of latter. Spermiducal funnel about twice as long as wide; with 

 thin, reflected collar; sperm duct in 12 only, much coiled. Penial bulb of 

 simple lumbricillid type; but one set of cells in body of bulb. Spermathecae 

 spindle-shaped; without distinct separation between ampulla and duct; no 

 diverticula; two groups of glands at ectal opening; extending caudo-dorsad to 

 union with corresponding part of opposite spermatheca; common duct leading 

 to lumen of alimentary canal; diameter of ampulla about twice that of duct. 



DISCUSSION. Slight differences between the Canadian specimens and 

 those described by Eisen from Nova Zembla exist in one or two sets of organs. 

 The spermiducal funnel in the former is not as stout as Eisen indicates in his 

 figure, and the ampulla of the spermatheca is less distinctly set off from the 

 duct, but these are differences of degree and are of little significance. Eisen 

 figures several glands at the ectal openings of the spermathecae but the Canadian 

 specimens have only two. 



DISTRIBUTION. Aside from the original discovery of a few specimens of 

 Henlea ochracea in Nova Zembla, nothing has hitherto been known concerning 

 its distribution. The discovery of enchytraeids apparently belonging to this 

 species in arctic North America is therefore a matter of interest and indicates 

 for this annelid a wide distribution. 



Henlea arctica, n. sp. 



A collection made July 2, 1915, from the mud at the margin of a tundra 

 pond, Bernard harbour, Northwest Territories, contained six enchytraeids, 

 two of which were mature. These annelids show a combination of characters 

 which does not seem to agree with descriptions of species already known. In 

 some respects, they appeared to resemble certain poorly described species and 

 incomplete descriptions have made the determination very puzzling, but the 

 lack of complete agreement has led to the final conclusion that these worms 

 must be regarded as representing a new species. 



