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at the last Meeting, and entitled, " Researches tending to prove the 

 Non- vascularity of certain Animal Tissues, and to demonstrate the 

 peculiar uniform mode of their Organization and Nutrition." By 

 Joseph Tovnbee, Esq. Comm'unicated bv Sir Benjamin C. Brcdie, 

 Bart., F.R'.S. 



In the inti"oduction to this paper, the author first speaks of the 

 process of nutrition in the animal tissues which are pervaded by 

 ramifications of blood-vessels ; pointing out the circumstance, that 

 even in them there is a considerable extent of tissue which is nou- 

 rished without being in contact with blood-vessels. Tlie knowledge 

 of this fact leads us to the study of the process of nutrition in the 

 non-vascular tissues ; which tissues he divides into the three fol- 

 lowing classes ; namely, first, those comprehending articular carti- 

 lage, and the cartilage of the different classes of fibro- cartilage. 

 Under the second head he comprises the cornea, the cr^'StaUine 

 lens, and the vitreous humour; and, under the third, he arranges 

 the epidermoid appendages : viz. the epithelium, the epidermis, nails 

 and claws, hoofs, hair and bristles, feathers, horn and teeth. 



The author then proceeds to show that the due action of the 

 organs, into the composition of which these tissues enter, is incom' 

 patible with theu' vascularity'. In proof of the non-existence of 

 blood-vessels in these tissues, he states that he has demonstrated, by 

 means of injections, that the arteries, which previous anatomists had 

 supposed to penetrate into tiieir substance, either as serous vessels, 

 or as red-bloodvessels too minute for injection, actually terminate in 

 veins before reaching them ; he also shows that around these non- 

 vascular tissues there are numerous vascular convolutions, large 

 dilatations and intricate plexuses of blood-vessels, the object of which 

 he believes to be to arrest the progi'ess of the blood, and to allow a 

 large quantity of it to circulate slowly around these tissues, so that 

 its nutrient Hquor may penetrate into and be diffused through them. 

 The author states that all the non-vascular tissues have an analo- 

 gous structure, and that they are composed of corpuscles, to which 

 he is induced to ascribe the perfoiTiiance of the veiy important func- 

 tions in the process of their nutrition, of circulating throughout, and 

 perhaps of changing the nature of thenutiient fiuid which is brought 

 by blood-vessels to their circumference. The author then brings 

 foi'ward facts in proof of the active and vital properties of these cor- 

 puscles, and concludes his Introduction by stating, that it appears 

 to him, that the only difference in the mode of nutrition between 

 the vascular and the non-vascular tissues is, that in the former, the 

 fluid vrhich nourishes them is derived from the blood that circulates 

 throughout the capillaries contained in their substance : whilst, in 

 the latter, the nutrient fluid exudes into them from the large and 

 dilated vessels that are distributed around them : and that in both 

 classes, the particles of which the tissues are composed derive from 

 this fluid the elements which nourish them. 



The author then enters on an exaniination of the structure and 

 mode of nutrition of the several tissues of each of these three classes. 



