The use of the term to mean the individualized nucleated mass of living protoplasm, which, whether with or without a limiting membrane, primitively forms the proximate histological element of the body of every organism, dates from the second quarter of the i9th century.
Most of the specimens had formed a zone of secondary wood and phloem resembling the corresponding tissues in a recent Cycad; the similarity extended to minute histological details, as is shown especially in H.
The chief work has been the detection of chronic changes in the cortex of the brain, by staining and other histological methods, in degenerative affections of this organ - Theodor Meynert (1833-1892), W.
Blochmann regards as coelomic, but it must be remembered that his interpretation rests largely on histological grounds, and at present embryological confirmation is wanting.
It is based upon the fact that the histological differentiation of the epidermis of their root is that generally characteristic of Monocotyledons, whilst they have two cotyledons - the old view of the epiblast as a second cotyledon in Gramineae being adopted.
From the histological examination of tumour cells there is no evidence to show that they resemble the protozoal unicellular organisms in occasionally passing through a sexual process of reproduction, i.e.
From them are developed two distinct types of histological elements; the genital cells and the cnidoblasts or mothercells of the nematocysts.
In the formation of these the tissues break down, and in course of time lose their characteristic histological features.
The features of histological structure seen in the Bryophytic series are such as we should expect to be developed in response to the exigencies of increasing adaptation to terrestrial life on soil, and of increasing size of the plant-body.
Protohydra is a marine genus characterized by the absence of tentacles, by a great similarity to Hydra in histological structure, and by reproduction by transverse fission.