APPENDIX. 787 



The pulp of the Malpighian body stands, as Remak pointed out, in 

 the relation of tunica adventitia to the arterioles ; it is composed of in- 

 different tissue, consisting of endoplasts imbedded in a homogeneous 

 periplast, and which may or may not become surrounded by cell-walls. 



The Malpighian body has no wall, but passes insensibly, as Wharton 

 Jones had already shown, into the fusiform fibres of the red pulp. 



We adduce evidence from Remak and Leydig that the Malpighian 

 bodies of other Vertebrata present similar relations, and that the spleen, 

 lymphatics, Peyer's patches and the glandules solitariw, the supra-renal 

 capsules, thymus, and pituitary body, belong to the category of the so- 

 called "vascular" glands, all consisting essentially of masses of indif- 

 ferent tissue contained in a vascular plexus. 



We proceed to show that the follicles of the tonsil are not closed, 

 but traversed by capillaries; and that it is a gland of the same class, 

 distinguished from a Peyer's patch only in the fact of its elements 

 being aggregated, not on a plane, but round a diverticulum of mucous 

 membrane. 



Finally, we suggest that the liver itself is but a huge tonsil a vascu- 

 lar gland, with what might be termed a false duct ; and we indicate the 

 agreement of this doctrine with the view taken by Dr. H. Jones with 

 regard to this organ, and we may add, with the recent beautiful re- 

 searches of Bernard. 



3. Corpora lutea. Prof. Kolliker does not appear to be acquainted 

 with the exact description of the structure of the corpora lutea, given 

 by Mr. Wharton Jones so long ago as 1843-4, in his " Report on the 

 Ova of Man and the Mammifera before and after Fecundation," " Brit, 

 and For. Med. Review," 1843, and in a paper entitled "Microscopical 

 Examination of an early Corpus Luteum," in the " London Med. Ga- 

 zette" for 1844. From the latter we extract the following passages, 

 premising that to the naked eye a section of this corpus luteum pre- 

 sented the appearance of a dark clot with a central membranous shred 

 from which processes radiated. 



" The body in question (early corpus luteum) is of a lenticular form, 

 about 6-10 inch in diameter, and about 4-10 inch thick, and projects on 

 the surface of the ovary by somewhat more than half its diameter. The 

 prominent part being covered merely by the indusium of the ovary, 

 the dark brown red color of the body shines through. Examined micro- 

 scopically the central membranous shred was found to present the fol- 

 lowing structure : 



" 1. On its free surface a fine film of tessellated epithelium. 2. In- 

 vested by this epithelium was a stratum of finely interwoven transpa- 

 rent fibres, with dark contours, somewhat like elastic tissue. 3. Out- 

 side all was a layer identical in structure with the stroma of the ovary, 



