1941 CATALOGUE OF FISHES OF TORTUGAS j? 



mine the fin formulas in detail was not possible, but the long spinous dorsal, 

 elevated lobes of dorsal and anal, and number of soft rays, together with the 

 well developed, widely forked caudal fin, marked the species rather well. 



W. H. L. 



The fin formulas as given in a published account are, D. XXX or XXXI, 12 or 

 13-VI; A. III,i2-VI. Body very elongate, depth contained about 15 to 17 times 

 in standard length; head about 5 to 5.5; scales missing; ventrals reduced to a 

 pair of very small spines. 



This species, as understood by most ichthyologists, occurs in various parts of 

 the Atlantic. It has generally been assumed that it inhabited deep water, but the 

 occurrence of the young in the waste of the bird rookery indicates that at least 

 part of the time the fish must be pelagic. S. F. H. 



Family TRICHURIDAE. Cutlass Fishes 



Benthodesmus atlanticus Goode and Bean 



Two specimens, 475 and 530 mm. long, are included in the collection. The 

 smaller one was taken in 205 to 283 fathoms, and the larger one in about 250 

 fathoms. 



The specimens, which are not in very good condition, were identified as Ben- 

 thodesmus atlanticus by Dr. Longley, which probably is correct, though the fin- 

 ray counts are lower than those given in the original description. It is difficult to 

 find the beginning of the anal in the specimens at hand, and that enumeration 

 may not be accurate, though the one for the dorsal should be correct. As the 

 type was taken from the stomach of a halibut, it probably was not in good con- 

 dition, and the counts based on it may not be very accurate. Dr. Longley counted 

 126 rays in the dorsal and 76 in the anal in the smaller specimen, and the larger 

 one according to my enumeration has 115 rays in the dorsal and about 70 in the 

 anal. As the counts given for the type are 154 for the dorsal and 100 for the anal, 

 it is necessary to make considerable allowance for errors and for variation to 

 identify the specimens in hand with the type. 



Caudal fin damaged in Tortugas specimens; peduncle very slender; head 

 rather broad and flat above, with a slight bony ridge at nape; lower jaw project- 

 ing strongly; mouth rather larger and jaws stronger than in the cutlass fish, 

 Trichiurus lepturus; teeth in anterior part of upper jaw very large, fanglike, the 

 lateral ones and those of the lower jaw smaller, yet fairly large; gill rakers small, 

 with minute points between the somewhat larger ones, about 5 + 7 of the larger 

 ones on first arch. 



The color of preserved specimens is silvery. 



The following proportions are based on the 2 specimens in the Tortugas col- 

 lection: Head 6.8, 7.1; depth in head 3.5, 3.4; snout (to tip of upper jaw) 2.4, 2.5; 

 eye 6.75, 6.9. 



Deep water of the Atlantic. S. F. H. 



