GENUS LAGENORHYNCHUiS. 83 



7. LAGENOEHYNCHUiS Gray. 



-=LiigeiiorIujnchus, Gniy, Zoology of the Erobus aud Terror, Irillj, p. 34. 

 <^DclpMnu!i of aiitliora prior to 1846. 



^Electra, Gray, SuppL Cat. Seals and Whales, 1871, p. 76. 

 ^Lcucoplearua, Gray, Suppl. Cat. Seals aud Whales, 1871, p. 78. 

 y>LageHorhi/nchus, Gray, Suppl. Cat. Seals aud Whales, 1871, p. 79. 



Professor Flower, in his recent admirable review of the family Del- 

 phinidiv, gives the following diagnosis of the genus La<jcuorhynchits : * 



Rostrum scarcely exceediug the leugth of the crauiuiu ; broad at the base and 

 gradually tapering toward the apex; depressed. Pterygoid boues normal, meetiug 



iu the middle line. Teeth small, not exceeding 4""" in diameter, "„ to ^. Vertebne 



very numerous, 80 to 90. Spinous and transverse processes of the lumbar vertebne 

 very long and slender ; bodies short. Externally, head with a short but not very 

 distinct beak. 



In the coarse of my studies upon the genus I have found no cause to 

 take exce[)tiou to this diagnosis, except so far as the number of teeth 

 and vertebrie are concerned. If the opinion that the Lagenorhynch us 

 thlcolea of Gray belongs to this genus is correct, the maximum number 

 of teeth must be set down as ^„ or ^^, instead of ||. On another page I 

 have shown that Lacj enorhynchus obliquidens, Gill, has but 74 to 76 ver- 

 tebrae. 



In addition to the characters summed up by Professor Flower, I have 

 observ^ed that the mandibular foramina in this genus are usually more 

 crowded together at the symphysis than iu Prodelphimis and Delphinus, 

 and are not preceded by so deep canals. The presence of an area of 

 bright color rather high up on the side, between the dorsal fiu aud the 

 flukes, likewise appears to be characteristic of the genus. 



The genus is, unquestionably, very closely allied to Prodelphimts. 

 The teeth are, on the ichole, more numerous, aud the vertebra3 less 

 numerous in the latter genus, but some species oiProdelphinus have a less 

 number of teeth and a greater number of vertebne than some species 

 of Lagcnorhynchus, aud vice versa. The projjortioual leugth of the beak, 

 the breadth and flatness of the intermaxillaj, appear to be the chief cra- 

 nial distinguishing characters which can be brought forward at present. 



The number of species which have been assigned to this genus is 

 quite large. In the following lists are included: (1) The species which 

 appear to me valid aud as properly belonging in the genus, and their 

 synonyms ; (2) species referred to the genus by previous writers, but 

 which I regard as belonging elsewhere; (3) nominal species. 

 1. Valid Species and their Synonyms. 



1. Lagenorliyiicluis aeutus Gray. 1828. 



Syu. Delx>hiiiiis i.schrichtii Schlegel. 1841. 

 Delphinus leucopleiiniH liMscli. 1843. 

 Lageiiorhyncltiis pertspicillatiis Cope. 1876. 

 Lagenorhjliichus guheruator Cope. 1876. 



* Proc. Zool. Soc. London, 1883, p. 511. 



