On the bush-dog (Icticyon venaticus, Lund.) / by William Henry Flower.

  • William Henry Flower
Date:
1880
Catalogue details

Licence: Public Domain Mark

Credit: On the bush-dog (Icticyon venaticus, Lund.) / by William Henry Flower. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    3/10 (page 71)
    / received at the British Museum from the Brazils under the name of Gynalicus melanogasler. It may here be noticed that the reference by the same author1 of Canis brachyotus, of which the skull and teeth are figured by Blainville (‘ Osteographie,’ gen. Canis, pis. viii. & xii.) to this species, is incorrect; but Van der Iloeven has given a good figure of the same parts2. Very recently Cope lias described (without figure) an extinct species from Oregon, which he refers to this group, under the name of Icticyon crassivultus3. In consetpience of the dental formula, and some superficial re- semblance in external form, this animal has often been placed bv systematists among the Mustelidse ; but its true position as a dog has been recognized by all who have closely investigated its struc- ture. The living specimen much recalled in appearance a young Fox, and had the manners of a playful puppy. It was a female, and at the time of death nearly adult. All the permanent teeth were in place ; but the canines were not fully protruded, and the epiphyses were not united to the ends of the long bones. The only decided character by which it has been separated generically from Canis, besides the shortness and broadness of the skull, is the reduction in development of the true molar teeth. In the upper jaw the posterior molar of Canis (—) is stated to be absent, and — is smaller and simpler than in the Dogs generally. In the lower jaw, whereas Canis has usually three true molars, Icticyon has but two ; and the last which is developed is con- siderably smaller than its homologue in the ordinary forms. This appears to have been the case in all the specimens hitherto ex- amined ; but the present example presents an interesting variation, as, in addition to the teeth usually described as being present, it has a pair of very small tubercular molars above, the crowns of which are divided into an outer and an inner cusp. The dental formula, therefore, is i. |, c. j, pm. (j) »/. ==^=-40, corresponding with that of Canis 'primoBVus of Bengal, constituting the genus Cuon ol Hodgson, to which animal Icticyon comes nearer, in the general loiin ol t le skull, than to any other of the group. The presence of these sma teeth may be an individual peculiarity ; or it may be that they are normally developed in the young animal, and are early deciduous, so that in the older specimens previously examined they have escaped notice. In any case they show a most interesting transitional cha- racter, and point to the fact that, in the reduction of the molar teeth, Icticyon is modified from a more generalized canine type. Another slight peculiarity in the dentition is that the inner tubercle of the upper sectorial is placed rather further from the anteiiot edge of the tooth than in Canis. 1 ‘Catalogue of Carnivorous, Pachydermatous, and Edentate Mammalia in e British Museum,’ by J. E. Gray, 18(»9, p. loo. „ V |...„fi1i;rl£ren aer 2 j Vn„ rW Uneven “Over bet geschbioht Icttcyon, \ ei Irnnck linen,’ Dcrdc Duel (Amsterdam, loot*], in n.nd Canidiv, Proa Acad. Nat. Sciences [3J the . . J. Van der Hooven, “ Over hot gcselii Koninkliike Akademie van Wetonschappcn, :l E. Cope, “On the Genera of Fclidro and Lamcliv-, Philadelphia, July 8th, 187b.