78 ME. I\ DAY ON THE HEBRIDAL ARGENTINE. 



being between and on the plates in small numbers, but no 

 accessory plates exist on it ; beneath, the disk is covered with skin 

 Spinules are found on the upper part of the arm, and the first and 

 second upper arm -plates are spined. The spines of the side arm- 

 plates project, and there are hooks ; there is one tentacle-scale. 

 These characters distinguish the form, and necessitate its entry 

 into a new genus, Polypholis. The species is Polypholis echinata. 



DESCRIPTION OF PLATE III. 



Fig. 1. The disk and part of the arms from above, magnified. 



2. The disk from below, magnified. 



3. The spinules from the disk, magnified. 



4. The arm spines and hooks, magnified. 



5. a, b, c. The tentacle-scale, magnified. 



6. Diagram of the mouth-shield, side mouth-shield, and angle of jaw. 



7. Polypholis echinata, nat. size. 



On the Hebridal Argentine. By Francis Day, F.L.S. 

 [Read March 4, 1880.] 

 (Plate IV.) 

 Argentina sPHYRiENA. 



Sphyrcena parva^ondeh i. p. 227, c. fig.; Gesner, pp. 883, 1061. 



Argentina, "Willughby, p. 229 ; Eay, p. 108 ; Artedi, Synon. 

 p. 17, and Genera, p. 8. 



Argentina sphyrcena, Linn. Syst. Nat. i. p. 518 ; Gmel. Linn, 

 p. 1394 ; Eisso, Ichth. Nice, p. 336, and Europ. Merid. iii. p. 462 ; 

 Cuv. Mem. Mus. i. p. 228, pi. xi. ; Nilsson, Skand. Fauna, Fisk. 

 p. 476; Gunther, Catal. vi. p. 203 ; Collett, NorgesFiske, p. 171. 



Argentina silus, jun., Nilss. Obs. Ichth. 1835, pp. 3-7. 



Osmerus hebridicus, Tarrell, Supp. Brit. Fishes, and ed. 2, ii. 

 p. 133 ; Eudd, Zoologist, 1852, p. 3504 ; White, Catal. Brit. Fish. 

 p. 79. 



Argentina Cuvieri and Yarrelli, Cuv. & Val. xxi. pp. 413, 418. 



Argentina hebridica, Nilss. Skand. Faun., Fisk. p. 474; Tarrell, 

 Brit. Fishes (ed. 3), i. p. 300 ; Gunther, Catal. vi. p. 203. 



Hebridal S?nelt, Couch, Fishes of the British Isles, iv. p. 297. 



Argentina decagon, Clarke, Trans. & Proc. New Zealand Insti- 

 tute, 1878, xi. p. 296, pi. xiv. f. 2. 



Stromsild, Christiania. 



B. vi. D. 10 (|). P. 14. V. 11. A. 12 (f). C. 19. L. 1.52. 

 L, tr. t Case, pylor. 5. 



