408 MR. G. E. DOBSON ON THE ERINACKID.E. [Mar. I, 



upwards and to the left side; and in the liver (fig. 5), which has a 

 much shorter and thicker caudate lobe (as indeed might be expected 

 in a comparatively much shorter animal). But very considerable 

 variability in the forms of both these organs is observable in the 

 different species, no two species agreeing closely. The intestinal 

 canal, however, in length and in its general construction is very 

 similar througiiout the whole family. 



The lungs are constructed very much on the same plan as in 

 Gymnura ; but they are comparatively smaller, as might be expected 

 in animals depending on their armour, and not on their speed, in 

 making their escape when attacked by enemies. The right lung is 

 divided more or less completely into three lobes; but the left is quite 

 undivided ; the azygos lobe is well developed and pyramidal in out- 

 line, the apex of the pyramid, not the base, as in Gymnura, being at 

 its lower extremity (fig. 7, p. 400). 



The uterus (fig. 9, p. 401) scarcely differs in form throughout 

 the species. It exibits an advance in development ; for, although the 

 cornua are even longer than in Gymnura, there is a true corpus 

 uteri, into which they open at right angles. The os uteri is not 

 enclosed in a hood, as in G. rofflesii ; but one or two deep folds occupy 

 the uterine extremity of the vagina, which are so large that, as John 

 Hunter remarked, they ajipear at first as if they were the os uteri '. 



A review of the anatomy of the species of Erinaceus not only adds 

 valuable aid in attempting their systematic arrangement, but also, 

 when we compare it with that of Gymnura, leads to the conclusion 

 that they are but differentiated forms of some animal of which we 

 have very probably a close representative in G. rafflesii, which we 

 may expect will be hereafter proved to be a very ancient form, 

 perhaps one of the sole survivors of a once widely extended group 

 of predaceous Insectivora. 



EXPLANATION OF THE WOODCUTS. 



Fig. 1. Crown of first upper molar, right side, of Gymnura r^y^fs//, showing the 

 fifth central cusp, T\hich is eoiiueeted by a j\^-shaped ridge \vith the 

 bases of the two internal cusps. 

 2, 3. Stomach of Gymnura rajflcs/i and of Erinaceus eurojmiis (reduced). 

 4, 5. Posterior surfaces of livers of the same species (much reduced). 

 6, 7. Lungs of the same species, from below, half natiu-al size. 

 8, 9, Uteri and vagina; of the same species. The uterus of each is .shown 

 in section ; the vaginal walls are divided and retieeted. The 

 diflerent positions of the urethral aperture («(/•) in the two species 

 is noticeable, and the presence in G. rafficsii of a hood concealing 

 the OS uteri (o ii). 

 10, 11. Anterior halves of the skulls of Erinaceus etiropmis and E. blwnfordi 

 (enlarged). 

 Figures 1, 10, 1 1 are from enlarged drawings by Mr. Mintern, from specimens 

 in the collections of the British Museum and of Mr. W. T. Blanford, F.K.S. ; 

 figures 2-9 have been reduced by Mr. Smit from drawings by the author. 



' As no specimen of a male Gymnura has yet been obtained for examination, 

 the male organs of Erinaceus are not referred to here ; they will be found fully 

 described in the work referred to on p. oSO, as well as all other parts which 

 ha\e been but cursorily touched upon or' are not described in this abstract. 



