58 RECORD OF CURRENT RESEARCHES RELATING TO 



Of the two kinds of spermatozooids found, the one, the so-called 

 vermiform spermntozooid, is a long tube, whose finer end terminates 

 in a slight enlargement, the other, broader one ending in a tuft of 

 cilia. Their movements present a remarkable difference from those 

 usually observed in spermatozoa ; they are replant, and move by a 

 slow, serpentine undulation of the body, aided by irregular vibrations 

 of the cilia, and by a right-and-left movement of the head. 



The filiform spermatozooids, on the other hand, possess a cork- 

 screw-shaped cephalic end made up of fine bends, and a fine, thread- 

 like caudal termination. They are half the length of the vermiform 

 kind, and move very rapidly, by means of a rotation of the cephalic 

 end, together with vibrating oscillations of the caudal end. 



With regard to the development of these forms, which both occur, 

 together with mother-cells, in April in the testis, they may be 

 distinguished at an early stage. In sections of the testis, taken at 

 the beginning of April, were recognized mother-cells of two different 

 sizes, attached to its wall. The mother-cells contain, near their 

 attached side, a dark oval nucleus (the ^'■principal nucleus" ; so named 

 iu Helix) ; round this lie a number of smaller nuclei in the protoplasm. 



The evolution of spermatozoa from these cells is first traced at a 

 somewhat later stage, in which their attached side is shown by the 

 action of osmic acid to be full of granular, fatty matter, whifih veils 

 the nucleus when stained. In al ohol preparations this, the prin- 

 cipal nucleus, is seen to be long and oval, and to be surrounded by a 

 number of smaller nuclei enclosed in cells clustered jacemosely ; 

 these cells are the spermatoblasts. The disproportion between the 

 two sizes of generative masses is still maintained. The smaller 

 spermatoblasts now undergo a very rapid transformation, resulting 

 in the production of bundles of the smaller, filiform, male elements 

 arranged parallel with each other. The complete development of 

 the larger, vermiform, elements, follows this circumstance thus. At 

 the time at which the small ones are fully developed (the end of 

 April), the spermatoblasts of the former are pyriform, nucleated cells, 

 connected with the gland-wall by a short pedicle, and are distinct 

 from each other at their distal ends, while they meet proximally 

 in the mass which contains the principal nucleus. Towards the end 

 of May, some bunches present spermatoblasts much elongated, into 

 a racquet-like shape, whose volume and the distinctness of whose 

 nuclei has become less, and on whose larger (distal) ends small 

 ciliated appendages occur. Another bunch at this time, looked at as 

 a whole, has the appearance of a bundle, which is made up of very 

 elongated sub-cylindrical spermatoblasts, containing traces of nuclei 

 at the free ends, which are slightly dilated, and now carry manifest 

 cilia. Finally, side by side with the last, may be found bunches of 

 completely developed spermatozooids, almost perfectly cylindrical, 

 with no traces of nuclei, still implanted in the basal mass containing 

 fatty granules. 



Thus the two kinds of spermatozooids are developed independently 

 at somewhat difierent periods. A more careful study of the larger 

 kind by teasing and examination of the fragments of the gland, 



