HY PEXODON—-HYPODON. 341 
Hypexodon Rarinesqur, 1819. Chiroptera, Vespertilionide. 
Journ. de Physique, LX XXVIII, 417, June, 1819. 
Type: Vespertilio mystax Rafinesque, from Kentucky. 
Hypexodon: $z0, under; €&, six; 65@v=ddovs, tooth—in allusion to the six 
lower incisors. * 
Hypisodus Corr, 1873. Ungulata, Artiodactyla, Agriochceride. 
Syn, New Vert. Tert. Colorado, p. 7, Oct., 1873; Bull. U.S. Geol. & Geog. Sury. 
Terr., No. 1, p. 26, 1874; Ann. Rept. Geol. & Geog. Surv. Terr., for 1873, 
501—502, 1874. 
Type: Hypisodus ringens Cope, from the Oligocene of Colorado. (In 1874 this 
name was considered a synonym of Leptauchenia minima Cope.) 
Extinct. ‘‘ Represented by the entire symphysis and portions of both mandibular 
rami." 
Hypisodus: ózó, under; 760s, equal; ó0ovs, tooth—in allusion to the lower teeth 
(except the true molars), which were described as ‘subequal.’ 
Hypocetus LvprEkkEn, 1894. Cete, Physeteridze. 
[ Nat. Science, IV, No. 24, p. 125, Feb., 1894—nomen nudum]; Anal. Mus. La Plata, 
Paleont. Argentina, II, 1893, art. No. II, 7-8, pl.rir, Apr., 1894; AwEGHiINO, 
Revista Jardín Zool., Buenos Ayres, II, entr. 7, p. 193 footnote, July 15, 1894 
(date of publication). 
New name for Mesocetus Moreno, 1892, which is preoccupied by Mesocetus Van 
Beneden, 1880, a genus of Balzenidze. Antedated by Diaphorocetus Ameghino, 
Feb., 1894. 
Hypocetus: 670, under; «?jroc, whale. 
Hypocoelus Amecuino, 1891. Edentata, Megatheriidze. 
Revista Argentina Hist. Nat., I, entr. 4*, 250, Aug. 1, 1891. 
New name for Cwlodon Lund, 1838, which is preoccupied by Coelodon Latreille, 
a genus of Coleoptera described by Serville in 1832. 
Hypocoelus is preoccupied by Hypocoelus Eschscholtz, 1836, a genus of Coleop- 
tera, and is antedated by Nothrotherium Lydekker, 1889. 
Extinct. 
Hypocoelus: ózó, under; «ozAos, hollow. 
Hypoderma I. Grorrroy, 1828. Chiroptera, Pteropodid:e. 
Dict. Class. Hist. Nat., XIV, 706, 707-708, Sept., 1828; É. Grorrroy, Cours Hist. 
Nat., Mamm., 13° lecon, for June 27, 1828,+ 28-31. 
Hypodermis BuvrH, in Cuvier's Animal Kingdom, 1840, 69; new ed., 1849, 69; 
new ed., 1863, 57. 
Type: Cephalotes peronii I. Geoffroy ( — Pteropus palliatus E. Geoffroy ), from Timor. 
Name preoccupied by Hypoderma Latreille, 1825, a genus of Diptera. Replaced 
by Dobsonia Palmer, 1898. 
Hypoderma: $zó, under; óéoua, skin—so named **on account of the complete 
dorsal insertion of the membranes of its wings."  (Brvrm.) 
Hypodon HarpEwaN, 1841. Cete, Physeteridze. 
Proc. Acad. Nat. Sci. Phila., I, No. 8, p. 127, Nov., 1841. 
New name for Diodon Lesson, 1828, which is preoccupied by Diodon Linn:eus, 
1766, a genus of Pisces; and by Diodon Storr, 1780, a genus of Delphinid:e. 

, 
* Agassiz erroneously gives the derivation as: op, above; £8, six; 66@v=d6do0vs, 
tooth (Nomencl. Zool., Mamm., 1842.) 
t ‘Ce volume, quoique daté de 1829, a été tout entier publié, en vingt livraisons, 
pendant l'année 1828." (I. Grorrroy, Vie, Travaux, etc., d' Étienne Geoffroy 
Saint-Hilaire, 422, 1847.) 
