1. SALMO. 79 



the length of the snout, and one-fifth of its distance from the end of 

 the opercidum. Maxillaiy strong, broad, extending far behind the 

 eye. Teeth strong ; vomerine teeth in a single series anteriorly, and 

 in a double one posteriorly. Prffioperculum rounded. The distance 

 between the end of the snout and the occiput is one-half of that 

 between occiput and origin of dorsal fin, the origin of the dorsal fin 

 being midway between snout and end of adipose fin. The fi-ec por- 

 tion of the tail is long and slender. Fins moderately developed ; 

 caudal subtruncated. Sides of the head with large, oblong, blackish- 

 brown spots, some confluent into bands. Bodj' and fins immaculate. 

 {H. jf K.) 



Eiver Sala, a tributary of the Isonzo. 



8. Salmo obtusirostris. 



River-Trout of Dalmatia (and of Italv). Trotta. 

 Trotta, Salvicmi, fol. 97, c. fig. fol. 96; cop. by WUlugbby, tab. N. 3. 

 ? Salmo marmoratus, Cm\ Reyne Anim. 



Salar obtusirostris, IfecJcel, in SUzf/shvr. Akad. Wiss. Wien, 1852, viii. 

 p. 367, taf. 9 ; Heck. 4'- Ktier, Siissicasserf. p. 253, fig. 139. 



D.14. A. 11-12. P. 13. V. 9. L. lat. 101-103. L.transv. 20/21. 



Head rather short, with the snout very convex and obtuse, body 

 stout. Prseoperculum with the lower limb distinct. Maxillary very 

 broad and short, in specimens 15 inches long not extending to the 

 hind margin of the eye. Dentition rather feeble : the vomerine 

 teeth form a double series, and are j^ersistent throiighout life. The 

 length of the pectoral is more than one-half of its distance from the 

 ventral ; caudal slightly emarginate in specimens of the length indi- 

 cated. Coloration similar to that of S. fario. {Heckel.) 



A non-migi-atory species from the Dalmatian rivers, and the Tiber ; 

 rarely much exceeding a foot in length. 



V. The Alj)ine region of Central Europe. 



The great lakes of the Alpine region of Central Europe are inha- 

 bited by Trout which do not descend to the sea, but sojourn in those 

 fresh waters after having ascended theu- affluents and deposited theu- 

 spawn. Their specific distinction has been a matter of great diffi- 

 culty ; and prcArious authors have evidently frequently confounded 

 the species, attributing characters to one originally taken from 

 another. Heckel, Kner, and Rapp had prepared the way to a better 

 understanding of these fishes, when Siebold finding that a number of 

 mdividuals are not sexually developed, and that this condition of the 

 sexual organs is accompanied by certain external peculiarities, ex- 

 pressed it as his opinion that all these fishes were of but a single 

 species. However, when we consider that, if this were true, the 

 number of the pyloric appendages must be assumed to vary from 40 

 to 100, that of the vertebrae from 57 to 61, that the form of the prae- 

 operculum also must be subject to extraordinaiy variation, we hesi- 

 tate before we adopt so bold an opinion. Variation to such a degree 

 is not confirmed by the examination of Salmonoids of other countries. 



