ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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(2) Within the cell-plasma, between the nuclei, intracellular vacuoles 
of different sizes appear, and cell-boundaries are indistinct, e. g. Mono- 
stomum trigonocepJialum. 
(3) The vacuoles are so large that the protoplasm forms only a 
sheath of the cell, and the elements form a connected meshwork in 
which each mesh represents a cell, e. g. Mon. reticulare. 
(4) The vacuoles may fuse, and the cortical sheath is burst and 
torn at intervals, e. g. Mon. proteus. 
The most important modifying factor is the formation of vacuoles, 
and it must be noticed that different types may occur in tbe same 
species at different ages and times, or at different parts of the body. 
The accumulation of water in the vacuoles probably brings about 
turgescence of cells and tension of the skin, and thus facilitates loco- 
motion. 
Secondly, as to the cuticle, which serves for the insertion of the 
parenchyma muscles, Herr Walter regards it as a product of the 
subjacent subcuticula, and that again as a product of the chromato- 
philous subcuticula cells. Thirdly, as to the so-called “ large cells ” of 
Trematodes, often regarded as ganglionic, they are also derived from 
the chromatophilous cells, and are merely stages in transition towards 
parenchyma. 
Body-parenchyma of Trematodes.* * * § — Herr A. Looss finds that this 
tissue, apart from what may be deposited within it, is originally formed 
of entirely homogeneous cells. In the adult state the firm and thick 
membranes of these cells persist, closely appressed, cemented by inter- 
cellular substance, forming a meshwork with colourless plasmic fluid in 
the meshes. The subcutaneous stratum of indifferent cells corresponds 
anatomically and physiologically to the cambium in plants. As to the 
skin, the -author regards it as a secreted product, and is inclined to derive 
it for the most part from the body-parenchyma. 
Trematodes of Reptiles and Amphibians.t — Dr. P. Sonsino gives a 
list, with some descriptions, of these parasites. Thus, in Emys lutraria 
there is Polystomum ocellatum , in Chelone caretta four species of Distomum , 
e. g. D. cymbiforme , in the chamaeleon three doubtful species of Distomum , 
in the edible frog Amphistomum subclavatum , Distomum vitellilobum , D. 
ovocaudatum , D. clavigerum, D. cygnoides, D. endolobum , D. variegatum , 
CodonocepJialus mutabilis , and so forth. 
The predominant Taenia of Rome.J — Dr. G. Alessandrini asks what 
species of Taenia predominates in Rome and the surrounding province, 
and answers that it is T. mediocanellata or saginata. But none seems 
very abundant. 
Brazilian Helminthology.§— Dr. P. S. de Magalhaes, in his first 
note, gives a description of Linstow’s species Taenia cuneata , from the 
duodenum of the Fowl. There are certain differences, however, in the 
two descriptions, but these the author ascribes to variations in the length 
* Ber. K. Sachs. Ges. Leipzig, 1893, pp. 10-34. 
t Atti Soc. Tosc. Sci. Nat., viii. (1893) pp. 183-90. 
x Boll. Soc. Bom. Stud. Zool., ii. (1893) pp. 83-6. 
§ Bull. Soc. Zool. France, xvii. (1892) pp. 145 and 6. 
