Prof. F. A. Smitt un the Genus L}xodes. 57 



liy the accessiule authors, for the greater number of local 

 varieties and forms already described as distinct species, [ 

 was unable to recognize more than four true species, viz. 

 Lycodes reticiiiatas, L. Vahlii, L. Sarsii, and L. miawna. 

 Now, in determining the very valuable collections brought 

 home from Greenland this year by the Nathorst expedition, I 

 find these views fully contirmel. Lycodes perspicillam 

 { = L. Rossi) is the young stage of L. reticulatus, Li/codes 

 cjracHis that same stage of L. Vahlii. Lycodes pallidas was 

 identified by Lonnberg with Lj. frigidus* [ = L. reticuhitus), 

 but by Collett t vvith L. gracilis { = L. Vahlii)] thus these 

 two authors, by their difference of opinion, strengthen the 

 doubts {:s to the validity of the distinction based upon the 

 cbaracteristics used by themselves. 



As in the near future I shall return to a fuller treatment of 

 the collection of fishes from the last Nathorst expedition, I 

 will here give only a key to distinguish the species, in 

 accordance with the chai-acteristics supplied by my new 

 materials : — 



A. Length of the head more than 29 (30) per cent. 



of the length of the tail. — Subgenus Lycodes. 



a. Length of the head more than 42 per cent. 



of the length of the tail Lycodes reticulatus. 



h. Length of the head less than 40 per cent, of 



the length of the tail Lycodes Vahlii. 



aa. Length of the head more than 22 per 

 cent, of the total length and usually more 

 than 36 per cent, of the length of the 

 tail. — Forma arctica ( T'rt/(/(V typica). 

 hh. Length of the head usually less than 22 

 per cent, of the total lengtJi and less than 

 36 per cent, (most usually less than 33 

 per cent.) of the length of the tail. — 

 Forma borealis (yracilis, auctt.). 



B. Length of the head less than 29 (28) per cent. 



of the length of the tail. — Subgenus Lycen- 

 che'ys. 

 ft. Height of the body at the beginning of the 

 anal tin less than 5 per cent, of its total 

 length Lycodes mureetm. 



b. Height of the body at the beginning of the 



anal tin more th;in 5 per cent, of its total 



length Lycodes Sarsii. 



* Under this name Lonnberg (" Notes on the Fishes collected during 

 the Swedish Arctic Expedition to Spitzbergen and King Charles Laud, 

 1898," Bih. Sv. Vet.-Akad. Ilandl. 1899, Bd. 24, Afd. iv. no. 9, p. 24) 

 described a specimen with all the characteristics of Lycodes reticulatus. 



t " Contribution to the Knowledge of the (ienus Lycodes, Reinh. — TI. 

 Lycodes gracilis, M. S.irs,'" Vid. Selsk. Skriften, Christiauia, I, Math.- 

 NaUirv. Kl. 1899, no. 6, pp. o and 10. 



