FISHERY BULLETIN: VOL. 81, NO. 1 



adult complement of 10+9 principal caudal rays 

 is consistently ossified in 29-30 mm larvae, but 

 secondary caudal rays are not completely de- 

 veloped until after transformation. In a 30.6 mm 

 specimen (Fig. 4f), ural centra 1 and 2 are ossify- 

 ing as are two neural spines associated with 

 preural centra 1 and 2 and haemal spines associ- 

 ated with preural centra 1-4. The bases of pre- 

 ural centra 1-8 are beginning to ossify. 



In a 35.1 mm transformed juvenile, all centra 

 of the caudal complex, preural and ural, are ossi- 

 fied as is the specialized neural process (Hollister 

 1936) dorsad to Ui (Fig. 4g). Ural centra 1 and 2 

 are still separate. Neural and haemal spines and 

 principal and secondary caudal rays are fully 

 ossified. The hypural bones are separate and 

 autogenous in this specimen. A 51.6 mm juvenile 

 has ural centra 1 and 2 fused into a single uro- 

 style (Fig. 4h). The single epural is beginning to 

 ossify and hypural bones 1-3 are fused together 

 at their bases and ankylosed to the urostyle. 

 Hypural bones 4-7 are still autogenous in this 

 specimen. In this specimen, the 10 superior prin- 

 cipal caudal rays are distributed as follows: 

 hypural 7, one ray; hypural 6, two rays; hypural 

 5, four rays; hypural 4, three rays. The inferior 

 nine principal rays included one ray on hypural 

 3, five rays on hypural 2, two rays on hypural 1, 

 and one ray on the posteriormost haemal spine. 

 During the development of the caudal fin, the 

 ventralmost principal caudal ray is associated 

 with hypural 1; it apparently is displaced to ar- 

 ticulate with the ultimate haemal spine in some, 

 but not all, juvenile specimens. 



Dorsal and anal fin rays ossify rapidly during 

 transformation as do pectoral and pelvic fin rays 

 (Table 3). It was not possible to follow the se- 

 quence of ossification of individual rays in these 

 fins. The adult complement of dorsal, anal, and 

 pelvic fin rays is present on the smallest trans- 

 formed specimen. The adult complement of eight 

 to nine pectoral rays, however, is not present in 

 all transformed specimens examined. Scales are 

 not present in a 55.0 mm juvenile, but they are 

 reported to be deciduous (Hart 1973), and hence, 

 may have been lost during capture. 



COMMENTS ON THE VALIDITY OF 



THE GENUS LEUROGLOSSUS GILBERT 



AND THE SPECIFIC STATUS AND 



NAME OF L. SCHMIDTI 



The results of this study offer support for the 

 validity of the genus Leuroglossus Gilbert which 



has been questioned. Gilbert (1890) erected the 

 genus Leuroglossus in the family Argentinidae 

 for specimens from the Gulf of California that he 

 described as Leuroglossus stilbius. Chapman 

 (1943) reviewed Leuroglossus Gilbert, removed it 

 from Argentinidae, and placed it in Bathylagi- 

 dae. Cohen (1964) synonymized Leuroglossus Gil- 

 bert with Bathylagus Giinther. Borodulina (1968) 

 stated Leuroglossus lacked an orbitosphenoid 

 bone, although Cohen (1964) said it was present 

 in Leuroglossus and used its presence as a gener- 

 ic character for Bathylagus. Borodulina (1969) 

 later described the osteology of L. schmidti and 

 compared it with B. paeificus (based on Chap- 

 man 1943). She stated that Leuroglossus, in con- 

 trast to Bathylagus, lacked an orbitosphenoid, 

 possessed teeth on the palatine, had three den- 

 ticles on the last pharyngobranchial, and pos- 

 sessed antorbitals. Ahlstrom (1969) described 

 differences in the movements of oil globules be- 

 tween Bathylagus and Leuroglossus eggs which, 

 with the lack of an orbitosphenoid in Leuroglos- 

 sus (as reported by Borodulina 1968), he felt, lent 

 additional support to the validity of Leuroglossus 

 as a genus distinct from Bathylagus. 



My samples of Leuroglossus lacked an orbito- 

 sphenoid, whereas those cleared and stained spec- 

 imens I examined of Bathylagus did possess an 

 orbitosphenoid. Specimens of B. paeificus, B. 

 ochotensis, and B. milleri I examined lacked 

 teeth on the pharyngobranchials, whereas Leuro- 

 glossus possesssed three teeth on the fourth 

 pharyngobranchial. 



Based in part on the lack of an orbitosphenoid 

 in Leuroglossus, the presence of one in Bathyla- 

 gus and the differences in the movements of oil 

 globules in the eggs of these two genera, as re- 

 ported by Ahlstrom (1969), I follow Borodulina 

 (1969) and Ahlstrom (1969) in considering the 

 two genera distinct. The number of valid genera 

 in the Bathylagidae and analysis of their rela- 

 tionships, however, await further study of the 

 entire family. 



This study provides additional evidence to rec- 

 ognize L. schmidti as a species distinct from L. 

 stilbius. Rass (1955) described a northern sub- 

 species, L. stilbius schmidti, from the Kurile- 

 Kamchatka Trench, based on morphometric 

 measurements which differed from measure- 

 ments described by Gilbert (1890). Cohen (1956) 

 synonymized L. s. schmidti with L. stilbius, as- 

 serting that the proportions used by Rass to de- 

 scribe L. s. schmidti were size dependent. Boro- 

 dulina (1968) pointed out that L. stilbius had 



36 



