ON THE STRUCTURE OF THE :\rALPIGHIAN BODIES 293 



Kolliker (' Mik. Anat' and ' Handbuch,' 1852), while denying the 

 entrance of the arterial twigs into the Malpighian bodies, states that 

 he had just succeeded in once observing a network of fine capillaries 

 in those of a cat, and he supposes that they will hereafter be dis- 

 covered in other animals. Finally, Mr. Wharton Jones speaks doubt- 

 fully of having observed a single capillary tube in the Malpighian 

 bodies of the sheep. (On blood- corpuscle-holding cells. — Brit, and 

 For. Med. Chir. Review, 1853). The existence of a special continuous 

 membrane investing the Malpighian bodies is affirmed by Ecker, 

 Gerlach, Kolliker, and Sanders. On the other hand, it is denied by 

 Henle (Allg. Anat. looi), and by Wharton Jones (1. c). 



With regard to the contents, Miiller's statements, as we have seen, 

 waver. Henle, Gerlach, Kolliker, and Sanders say that they are 

 composed of corpuscles suspended in a fluid. The quantity of the 

 latter is however, according to Kolliker, small. 



I may now proceed to communicate the results of my own obser- 

 vations upon the structure of the Malpighian bodies in Man, the 

 Sheep, Pig, Rat, and Kitten, and I will arrange what I have to say 

 under the three heads of — i. The distribution of the vessels of the 

 Malpighian bodies. 2. The structure of their substance (so-called 

 contents), or the Malpighian pulp. 3. The structure of their peripheral 

 portion, or so-called ' walls.' 



I. TJie Distribiition of the Vessels of the Malpighian Bodies. 



In all the animals above mentioned, I find it very easy to de- 

 monstrate, in almost every case, that one or more minute arterial 

 twigs enter and frequently subdivide in the substance of the Malpig- 

 hian body, making their exit on its opposite side, to terminate, finally, 

 by breaking up into minute branches in the pulp. Indeed, it is so 

 •easy to convince oneself of this fact, if a thin section of a fresh spleen 

 be examined under the simple microscope, that it is difficult to under- 

 stand how two opinions can exist upon the subject. The method I 

 have adopted is simply this : to such a section I add some weak 

 syrup, so as to retain the colouring matter in the blood-corpuscles 

 contained in the vessels, and thus to have the advantage of a natural 

 injection ; then, I either trace out the vessels into the Malpighian 

 bodies with needles, under a |-inch lens ; or, placing a glass plate 

 over the section, I apply a gentle and gradual pressure, just sufficient 

 to render the bodies transparent. It is then easy, by sliding the plate 

 with a needle, to cause the bodies to roll a little upon their axes, and 

 thus convince oneself, by the relative positions which the vessels and 



