ORGANS OF SECRETION. 609 



digital spaces in most ruminantia where we observe between 

 the hoofs a tubular and slightly ramified glandular cavity, 

 which affords an oily secretion of a strong and peculiar 

 odour, to lubricate and protect the hard extravascular hoofs, 

 and by which the carnivorous quadrupeds are better enabled 

 to trace the footsteps of their prey. Some of these rumi- 

 nating quadrupeds also exhibit simple cutaneous odorous 

 inguinal glands, opening on the surface near the mammae, 

 and developed in like manner from odoriferous parts of the 

 skin. The strongly aromatic musk of the musk-deer is 

 secreted by two glandular sacs, opening near the prepuce of 

 that animal. The spur of the ornithorhyncus was shown by 

 Meckel and Rudolphi to transmit through its tubular canal 

 the poisonous secretion of a large gland placed in each thigh. 

 In rodent quadrupeds there are numerous glandular follicles, 

 situate near the anus or near the prepuce, which secrete 

 strongly odorous, sebaceous, or oily fluids. Two plicated 

 glandular sacs are found on each side of the genitals of the 

 male and female beaver, which pour out, near the organ of 

 excitement, the well known fatty and resinous secretion, the 

 castoreum of medicine ; and the most conglomerate form of 

 the gastric glands is seen at the cardiac orifice of the stomach 

 in this animal and in the wombat, which aids the digestion 

 of their coarse vegetable aliment, and points out a closer 

 analogy between this part and the glandular stomach, or 

 ventriculus succenturiatus of birds. In many rodentia the 

 shut extremity of the long ccecum-coli is closely covered 

 with small simple glandular cryptee, which open into its 

 cavity, and similar rudimentary glands, in clusters of simple 

 follicles, occur in various parts of their alimentary canal. 

 Anal glands, secreting odorous substances, are also met with 

 in several of the marsupialia and pachyderma, but they are 

 most developed in the carnivorous quadrupeds, where their 

 secretion is remarkable for the intensity of its odour in the 

 civets, badgers, hyaenas, and some other genera. In the 

 elephant, similar odorous glands are seen in the region of 

 the temples, opening externally on each side by a small 

 round orifice, between the eye and the ear. 



But notwithstanding the infinite diversity of form, struc- 

 ture, and position of these secreting tubular membranes, 

 forming glands throughout the animal kingdom, and the 



PART VI. R R 



