NO. 2027. FISHES OF THE OENUS OSMERVS—FISK. 293 



OSMERUS STARKSI Fisk, new species. 



This species may be distinguished from the other two here dis- 

 cussed by the difference in the length of the pectorals. These fins 

 reach about three-fourths of the distance from their base to the 

 orighi of the ventrals, while in Osmems thaleichihys they extend to 

 or overlap the beguming of the ventrals, and in Osmerus attenuatus 

 they extend only haK the distance between their origm and the 

 msertion of the ventrals. The depth is 5 to 5f in the total length 

 without caudal (slightly less than that of Osmerus thaleicfithys, but 

 greater than m Osmerus attenuatus). The gill rakers are shorter, 

 coarser, and heavier than those of Osmerus thaleichtJiys, but are 

 longer and more slender than those of Osmerus attenuatus. The 

 dentition is weaker than that of either of the other species, and there 

 are two small teeth on the tip of the tongue, instead of a single large 

 one, as in Osmerus attenuatus. 



The head is contained 4 times in the total length without caudal. 

 The length of the snout in the head is contained 4 to i^ times. The 



03MEEU3 STARKSI, NEW SPECIES. 



maxillary is contamed twice m the head, and reaches nearly to the 

 posterior margin of the eye. The lower jaw is more blunt than in 

 Osmerus attenuatus, and projects slightly. The eye is contained a 

 little less than 4 times in the head, and its diameter is slightly less 

 than the mterorbital width. The interorbital space is contained 3^ 

 to 3f times in the head. The opercle is smooth, and slightly marked 

 at its edge with weak longitudinal striae. The gill rakers number 

 11 to 13 + 26 or 27 and the longest one is contained If times in the eye. 



The depth, in the length without caudal, is 5 to 5|. The depth of 

 the caudal peduncle is contained 2f to 3 times in the length of the 

 head. The scales along median line of back, from occipital region to 

 caudal, number 63 to 67. 



The number of fin rays is: Pectoral, 11 or 12; ventral, 8; dorsal, 

 10 or 11; anal, 18 to 20. The pectoral is contained 1^ to IJ times 

 in the head; the ventrals, 1^ times; the dorsal, 1^ to 1§; the anal, 

 2^; and the caudal, 1^. The distance of the dorsal from the tip of 

 the snout is more than one-half of the total length without caudal. 



