488 CETACEA. 



smooth and glistening spots (PL XXXV, l^g. 9) which, when bisected from the 

 mucous to the muscular coats, give a convex profile towards the uterine cavity. 

 They are nearly all on a level with the general mucous surface and occur either as 

 larger or smaller spots involving a number of ridgelets, or are confined to one patch 

 not surpassing the size of three or four of the pits or crypts. In the uterus before 

 me, which is soft, and little, if anything, contracted by the spirit in which it has 

 been preserved, the former predominate over the latter. In a square inch, taken at 

 haphazard from the dorsal wall of the left horn, eighteen of these spots were counted, 

 the largest being 0*19 inch in diameter and the smallest not more than O'Ol. They are 

 irregularly distributed all over the mucous surface, but many are so minute that the 

 uterine wall must be artificially stretched to exhibit them, and it is also important to 

 note that when the uterus contracts many are hidden by the bringing together of 

 the fine ridgelets of the mucosa, so that they are liable to be overlooked. The 

 majority have a rounded form, and the ridgelets and fine threads of the mucosa 

 radiate outwards from their circumference, but some have an elongated character, 

 and others are irregular in shape. 



In a uterus less mature than that from which the preceding description was 

 taken the smooth spots appeared to be much more numerous, but this was doubtless 

 due to the walls of the uterus being less expanded. It also showed the existence 

 of larger bare spots than any hitherto described, but these, however, were not numer- 

 ous and had no regular distribution, and, moreover, the largest was not more than 

 about half an inch in extent and of most irregular outline. 



When the bare spots of the ordinary character (PL XXXV, figs. 9 and 10) were 

 examined with a hand-lens, the appearance as if a small orifice existed was distinctly 

 visible in certain lights, fig. 10, occupying the centres of many of them and forcibly 

 recalling one of the leading features in the structure of the gravid uterus of the 

 sow. The mucosa over these nude areas is so delicate and transparent, that with the 

 artificial aid just mentioned, the utricular glands underlying it were easily discern- 

 ible. As the only tubular structures present in the wall of the uterus are blood 

 vessels and utricular glands, and as these apparent openings are not the mouths of 

 blood vessels, the conclusion is forced upon us, that if they are openings they are 

 mouths of the utricular glands, holding the same relation to the walls of the uterus 

 and to the bare spots in this Cetacean, as do the utricular glands in the uterus of 

 the sow and in those of other uteri with a diffuse placentation that have been 

 recently described by those masters in this field of anatomy, Ercolani and 

 Turner. 



Utricular glands. — When viewed under the microscope, a bare spot being 

 selected for observation in horizontal section (PL XXXVIII, fig. 8) these structures 

 are seen to be especially numerous all around it and are very tortuous and much 

 branched, the branches being of various lengths, rather tending to convolute and 

 to increase somewhat in diameter towards their blind extremities. They sometimes 

 divide dichotomously, and sometimes three branches wdll be given off at one point, 

 whilst in other instances a branch will give off only one short saccule from its 



