Gatiy Marine Laboratory^ St. Andrews. 129 



Heterochjmene robusia?, Arwidsson. 



A fraccment of the posterior end -with the funnel was 

 drcdj^ed in Norway in 1879, Stations 33 & 31'. 



The anterior end of this form somewhat resembles 

 Prfhvillella, but the median frontal process is less. Two 

 lateral notches and a median posterior notch occur in the 

 border of the cephalic plate. Tiiere are nineteen bristled 

 segments and five unarmed posterior segments. The funnel 

 has a large number of cirri, most being conical and short, 

 but others long. In a series Arwidsson gives from thirty short 

 and seven long to fifty short and five long, the latter, however, 

 sometimes reaching ten or twelve. In the present case there 

 are a total of thirty -five short and seven long. The stout 

 bristles have very narrow wings, and the tapered tips are 

 spinous. The more slender — which Arwidsson seems to call 

 tlie i)osterior ("-hinterin ") — are still more distinctly spinous. 

 Tiie hooks have curved shafts (PL III. fig. 5), boldly marked 

 shoulders, and rather long necks, the strong great fang 

 making nearly a right angle with the neck, and a small 

 interval occurring between its base and the gular bristles. 

 The moderately high crown has six to eight teeth — 

 Arwidsson says even ten. 



From Norway also comes a dried form somewhat re- 

 sembling Axiothella, but the anal fuunel appears to differ, 

 resembling rather that of Heteroclymene, having a large 

 number (about fifty-two) of small conical teeth, with about 

 eight longer cirri at intervals. Moreover, the funnel is 

 finely grooved internally. The hooks have a high crown 

 with eight or nine teeth above the great fang, and the gular 

 bristles arise close to the base of the latter and curve boldly 

 forward and upward. 



EXPLANATION OF THE PLATES *. 

 Plate IT. 



Fiy. 1. Hook of Praxillella A, Station 8. 'Porcupine.' x Zeiss oc. 4, 



obj. D, with 2 in. draw-tube. 

 Fiy. 2. Bristle of Praxillella near preetermissa, Bono Bay. X oc. 4, 



obj. D. 

 Fiy. 3. Hook oi Euclymene A, of! Ireland, x oc. 4, obj. D. 

 Fiy. 4. Lateral view of the anterior end of Nicomaclie {?) canadensis. 



Somewhat enlarged. 

 Fiy, o. Ventral aspect of the snout showing the mouth. Somewhat 



eularged. 



* I am indebted to the Carnegie Trust for artistic aid with these 

 Plates. 



Ann. & Mag. N. Hist. Ser. 8. Vol. xi. 9 



