365 
to the second category alluded to in the first paragraph of 
this paper, viz. the chemical and formal structure of the 
red blood-corpuscle) which present themselves are,—Can 
any of the chemical constituents of the stroma of the red 
blood-corpuscle be distinguished and identified by means of 
reagents under the microscope, and what is their condition 
in the living corpuscle? Does the red corpuscle of either 
mammal or other vertebrate possess a differentiated en- 
velope or wall? Is the nucleus of the frog’s red corpuscle 
merely a post-mortem product? Is there any trace of a 
nucleus in the mammalian red corpuscle? These questions 
are suggested by well-known researches. Another important 
question, viz. Whatis the nature of the Robertsian macula? 
is suggested by certainly the most remarkable contribution 
to the histology of the blood published of late years, that of 
Dr. Roberts of Manchester. I must confess that I am at a 
loss to understand how it is that his most important observa- 
tion, demonstrating a well-marked point (either normal 
or cadaveric) capable of taking strongly the aniline dye— 
in the walls of the red corpuscle of all vertebrata, both 
mammals and ovipara—have been so largely ignored. Rind- 
fleisch has, I believe, made a similar observation, but in the 
writings of Stricker, Schweigger-Seidel, and others, spe- 
cially dealing with similar phenomena, and in the article of 
Rollett, I find no reference to Roberts’ paper. Boettscher, 
it is true, discusses Roberts’ views and observations at length. 
In the following list I have given references to the more 
recent papers relating to the structure of the red blood-cor- 
puscle, and have briefly indicated the contents of the paper 
in each case. This list and the works cited in Rollett’s 
article, as well as the standard hand-books will furnish the 
reader with a nearly complete catalogue of the literature of, 
this subject. 
Gulliver, in Hewson’s works, ibique citata, Sydenham 
Society, 1846-47. (References to the older writers and to 
Mr. Gulliver’s other papers are here to be found, as well 
as observations on the properties of the corpuscles and the 
most extensive series of measurements of the vertebrate red 
blood-corpuscle.) 
Rollett, in Stricker’s ‘Handbuch der Histologie,’ or the 
Sydenham Society’s translation, ibigue citata. (References 
to numerous papers by Rollett himself and the Vienna 
school are given, and a discussion of most of the important 
points relating to the red corpuscle.) 
Briicke, “ Ueber den Bau der rothen Blut-kérper,” lyi Bd. 
