FISHES FROM BERING SEA AND KAMCHATKA. 



57 



The type of lucasi is 135 ram. long, hence larger than the smaller specimen of diceraits here reported on, 

 and but 20 mm. smaller than the larger one, yet the distinctive features of lucasi are maintained. 



The preopercular spine in lucasi is much shorter and much more slender, and bears but 2 or 3 large 

 distant hooked teeth; the supraorbital rim is sharp and thin, not massive and heavy, as in diceraus, 

 and the interorbital space is narrower and more shallowly concave (not deeper, as stated in the original 

 description); the occipital ridges are lower, and the posterior (nuchal) processes shorter and lower; the 

 anterior process of the preorbital entirely conceals and extends beyond the portion of the maxillary 

 over which it project";, and bears two very short spinous points totally unlike the pair of strong spines 

 present in diceraus: in advance of the two spinous points the preorbital develops a rounded lobe, which 

 also completely conceals a portion of the maxillary and has no representative in diceraus, although it 

 is present in the Japanese species Ceralocollus yiamiyci. The fin rays of the type and cotype of lucasi 

 are difBcult to determine, because of the mutilated condition of the specimens, and have been incor- 

 rectly given; in both specimens they are as follows: Dorsal, viii-14; anal, 12; pectoral, 18 on each side. 



The following comparative measurements in hundredths of length without caudal will indicate 

 some of the differences between the species: 



Through the courtesy of the authorities of the United States National Museum, we have had the 

 privilege of reexamining the cotype of C. lucasi (no. 48235, U. S. National Museum) and also the speci- 

 men from Avatcha Ray, Kamchatka, which was identified by Jordan and Gilbert with C. hicasi, and 

 from which the color description was taken (Fishes of Bering Sea, p. 459). The cotjpe agrees with 

 the type in all the characters above given by which the species may be distinguished. The preoper- 

 cular spine is short and bears distally on its inner edge three large hooked spines, of nearly equal size 

 and curved like the hooked spines of brambles; no smaller spines are interspersed, nor are there any on 

 the basal two-fifths of the spine. The interorbital area is narrow and shallowly concave, the orbital 

 rims not massive. A very wide process of the preorbital conceals the proximal portion of the maxillary, 

 its anterior free margin a rounded lobe, its posterior portion bearing a pair of short triangular projections, 

 corresponding to the two very pronounced preorbital spines in C. diceraus. The specimen from Kam- 

 chatka (no. 4S859, U. S. National Museum), which has been heretofore associated with C. lucasi, differs 

 widely from that species and is in fact a typical yovmg diceraus. Its measurements are given in the 

 third column of the above table. 



Myoxocephalus polyacanthocephalus (Pallas). 

 Unahiska, Atka, Agattu, and Attn Islands. 



Myoxocephalus jaok (Cuvier & Valenciennes). 

 Avatcha Bay, Kamchatka. 



Myoxocephalus stelleri Tilesius. 



Medni and Bering Islands, and Avatcha Bay, Kamchatka. 



Myoxocephalus niger (Bean). 



Agattu, Attn, Medni, and Bering Islands. 



