156 THE MICROSCOPE. 



Science, of Lond )!i, writes as follows on the "Structure of the Sper- 

 matozoon: 



I have examined a number of specimens of the human sperma- 

 tozoa, some taken from the testes twenty-four hours after death by 

 accident, others from twelve to twenty-four hours after coition; 

 these came by post and I could detect no material difference in their 

 structure, with the exception of the varying lengths of the tails ia 

 different specimens. I think something may be made of this, if 

 one could only get sufficient data to go upon. In all I found a 

 long, very fine filament, which required great care in the illumina- 

 tion to show it properly, as when after a good deal of trouble it was 

 shown well with the ^i^th immersion, I found I could readily see it 

 with the ^ijth oil and even the -ji^th oil immersion. The filament 

 is very fine and is connected to the tail by a mem.brane, which is 

 much wider than in the amphibia and allows it to move further from 

 the tail; it is also longer than in the amphibia and is more folded 

 in consequence. The mere fact of this discovery is pointed out by 

 the author. I suppose its significance will be determined by future 

 investigation. 



Attention should be called to the fact, that Ranvier has estab- 

 lished the extremely important and unexpected fact, as far as the 

 muscular coat of the sweat glands is concerned, that muscular tissue 

 in the mammalia is developed from the epiblast. 



Prof. Pouchet, of Paris, writes an article full of close research 

 on the much discussed origin of the "Red Blood Corpuscles." 

 After treating the lymphatic glands, the spleen, the marrow of 

 bones, the lymphoid patches in the mesentery, to which he says ob- 

 servers have tried to relegate this so-called haematopoietic function 

 and giving most excellent reasons for his non-belief in these theories, 

 he remarks there are yet left the supra-renal capsules and thymus, 

 and asks the question. Do they deserve also to be studied from the 

 same point of view? From this most interesting article, we draw 

 the following conclusions: It must be admitted that the origin of 

 the red blood corpuscles among adult mammals has not yet been 

 completely made out. Anatomists are divided between two prin- 

 ciple theories, some with Neumann and Bizzozero distinctly attrib- 

 ute to the red marrow this function in the economy — the produc- 

 tion of the haematids or red corpuscles and the provision for the 

 normal regeneration of the elements of the blood after accidental 



