132 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



the head is less than its distance from the root of the ventral, the origin of which is slightly 

 in front of that of the dorsal, the origin of the dorsal being over the posterior portion of the 

 root of the ventral, and also over the thirty-first scale in the specialized lateral line. Two 

 scales between lateral line and origin of the ventral; ventral broad, the length slightly 

 longer than that of longest dorsal. Pectoral fin moderate, extending less than half way 

 from its owi base to the root of the ventral, its length equal to half that of the head. Scales 

 on the lateral line not much enlarged, 07 in advance of the vent. The base of the dorsal 

 and anal scaly. Color brownish ; under surface of head lighter. 



Radial formula: D. 11; P. 16; V. 1, it; L. traus. 15 | 5. 



A single specimen was obtained by the Albatross from station 27-2, lat. 39° 13' N., long. 

 72° 1' W., at the depth of 591 fathoms. 



ALDROVANDIA, Goode and Bean, n. g. 



Lyopomi, with ventrals normal; no second dorsal fin; vertex scaleless; scales of lateral 

 line enlarged, provided with photophores. Head with pointed snout and prominent lateral 

 ridges. Anal fin moderate, high; its height one-third to one-fourth that of dorsal. Type 

 Halosaurus rost7-atus, Giinther. 



This genus is dedicated to Ulysses Aldrovandus, of Bologna, the founder of the first 

 natural history mnseum, whose name, strangely enough, has never been honored by asso- 

 ciation with a genus of animals or plants. 



ALDROVANDIA ROSTRATA,(Gunther). (Figure 154,) 



Halosaurus rostratus, GCntiier, Ann. ami Mag. Nat. Hist., 1878, II, 252. Challenger Report, xxu, 241, pi. 



lix, tig. 1>. 1887. 



"The length of the head much exceeds the height of the body. The snout very much 

 produced, spatulate, its preoral portion being more than one half of its length. Eye of 

 moderate size, its length being one-third of the postocular portion of the head, and consid- 

 erably less than the width of the interorbital space. Maxillary scarcely reaching the front 

 margin of the eye. The length of the head is a little more than its distance from the root 

 of the ventral, which is nearly entirely situated before the dorsal. Nearly all the scales are 

 lost, but some of the lateral line remain; they are much larger than the other scales; and 

 on the tail, where the lateral line approaches the lower profile, these larger scales fill up all 

 the space between the lateral line and the anal fin. 



" Distance of the snout from the mouth, SJ, lines; distance of the snout from the eye, 1 

 inch 3 lines; distance of the snout from the root of the pectoral, 2 inches 7 lines; distance 

 of the snout from the root of the ventral, 1 inches 10 lines; distance of the snout from the 

 origin of the dorsal, 5 inches 8 lines; distance of the snout from the vent, 6 inches 11 lines; 

 total length, 20 inches. 



" Bones of the head very thin; operculum smooth, covered with a very fine membrane. 

 The lower part of the side of the head is occupied from the snout to the gill opening by two 

 exceedingly wide muciferous channels, of which one takes its origin on the preorbital, the 

 other on the mandible, and which open behind at the gill opening by a common and very 

 wide aperture. Branchial apparatus as in the other species. The dentition is very similar 

 to that of Halosaurus macrochir, but the palatine patches are crescent-shaped and rather 

 widely separated from the pterygoid band. 



"The scales of the lateral line are about three times the size of the others, and about 

 twenty-four in number between the gill opening and the vent. Each bears a luminous 

 organ, vertically elongated and rhombic, but not extending to the upper and lower margins 

 of the scales. Light color, the lower part of the head and the gill cover black; abdominal 

 region blackish." 



Radial formula: B. 9; D. 10; V. 9, 10; L. transv. 13 | 6. 



The type, a single specimen, 22 inches long, is from the Mid- Atlantic Challenger station 

 63; depth, 2,750 fathoms. 



