XIX.—On the Histology of the Blood of the Larva of Lepidosiren paradoxa Part II. Hæmatogenesis

Abstract

In the first part of this memoir I described the structure of the corpuscles at a stage of larval development when the red cells were actively dividing and the blood contained several varieties of white cells. During the course of these more strictly cytological observations, it was impressed upon me that the great size of the elements and their very marked histological characters, combined with the simple character of the organisation of the animal, made Lepidosiren a very favourable case for the study of the first principles of Hæmatogenesis. I was specially interested in what may be termed a middle phase in the history of the blood. I refer to a period after the primitive corpuscles have acquired haemoglobin and there are leucocytes present, but before the blood-forming organs are unfolded. This stage lasts a relatively long time in Lepidosiren up to the differentiation of the spleen, as the liver takes no part in blood-formation at any period.