224 DR. MARTIN BARRY ON THE CORPUSCLES OF THE BLOOD. 



blance to certain states of the germinal vesicle figured in one of my former papers-}-. 

 Other conditions of the nucleus in some of the same epithelium-tables, equally 

 resemble the appearance of the discs or incipient cells succeeding that vesicle in the 

 ovum;}: : and in fig. 88. we have remarkable evidence of the appearances presented by 

 the contents of the ovum, and those of the epithelium-tables, being both referable to 

 the operation of the same process. This remark applies equally to blood-corpuscles, 

 apparently destined to enter into the formation of the epithelium, in fig. 95. 



115. The resemblance between corpuscles of the epithelium, and those of the 

 blood, is not confined to the part we have been considering. All the epithelium-cells 

 which have fallen under my notice present it more or less decidedly. Even those 

 collected from the surface of the tongue (fig. 92.), while they exhibit the greatest 

 irregularity in size and form, and considerable variety in the appearance of the 

 interior, present the same sort of discs, and the same division into minuter discs ; 

 many of them being also tinged with the same red colouring matter as is perpetuated 

 or reappears in the discs of other parts, more closely resembling corpuscles of the 

 blood. The nucleus also of the epithelium-cell from the tongue, is composed of discs ; 

 and I have seen it remarkably tinged with red. Among the cells from a furred 

 tongue, there were seen heaps of discs of a blood-red colour. The membrane of the 

 epithelium-cell — where a cell exists, as in fig. 92. — is obviously formed by the same 

 coalescence of discs, as that which we shall find to give origin to other membranes, 

 — for instance, to the membrane of the ovisac, figs. 170, 171, 172, h. 



116. The formation of what have been denominated epithelium-cylinders, I have 

 not had the opportunity of particularly following ; but may offer a few incidental 

 observations. In fig. 94 a. is the outline of a cell which was red throughout, and 

 filled with young epithelium-cells. The latter presented traces of division into objects 

 still more minute ; and this division at one part had really taken place. Traces of 

 division were observed also in the objects figs. 95. 99. and 100 ; the blood-red colour 

 of many of which, passed at one extremity nearly into black. Should these have 

 been, as I believe they were, incipient epithelium-cylinders, the observation, so far 

 from having realized the following conjecture of Professor Valentin, will stand in 

 direct opposition to it. " It appears," says he, "judging at least from the nuclei, as 

 though cilia-cylinders arose through the coalescence of two adjacent cells, and the 

 disappearance of the partitions. There are often seen, at least, in one and the same 

 cylinder, two nuclei, one on the other, or in part covering one another §." Were not 

 the two nuclei, seen by Valentin, produced — like those iA the figures, last referred 

 to — by division of a previously single nucleus? If so, it would seem that cilia- 

 cylinders arise, not by coalescence, but by division, like some of the Vorticellae ; which 

 they resemble also in the position of the cilia. 



f Compare with c, figs. 159, 160, 162, 169, in my Third Series on Embryology. Philosophical Transactions, 

 1840, Part II. J Compare with fig. 195 in my Third Series on Embryology, I. c. 



§ MiJLLER's Archiv, 1840, Heft II. p. 205. Note. 



