6o8 FOOT AND STROBELL. [Vol. XVI. 



to the expression of cell activity known as the male attraction 

 sphere, if it is the organic center of the sphere, forming with the 

 rays an organic connected whole, would not the spherical form 

 of the sphere be disturbed by the middle-piece moving away 

 from the center } In reality the form is no more disturbed than 

 is the form of the fertilization cone, when we find the head of 

 the spermatozoon quite out of the center of the cone. 



In photo. 19 the middle-piece is in nearly the center of the 

 sphere. (The contracted head of the sperm is in the adjacent 

 sections.) 



In photo. 20 we have a transverse cut through the middle- 

 piece, which bears a marked resemblance to a centrosome, 

 though its position in the sphere is eccentric ; the spherical 

 form of the sphere, however, remains undisturbed. (The con- 

 tracted head of the sperm is in the next section.) 



Photo. 21 shows a little later stage of development than 

 that of 18 ; the middle-piece is beginning to disintegrate, 

 and at a still later stage it has entirely disappeared. The 

 differentiation in color which one of us obtained between the 

 middle-piece of the spermatozoon and a distinct spherical body 

 within the male aster was probably due to the chemical change 

 which must take place at this time of disintegration. 



Photo. 22 shows about the same stage of development as 

 that of photo. 21 ; the middle-piece is beginning to disinte- 

 grate, showing three tiny spherical bodies. The middle-piece 

 and rays finally disappear at about the same time. 



Further Observations on the Origin of the Sper^n Grannies. 



Photos. 10 and 1 1 indicate an origin of the pathological sperm 

 granules different from that suggested by one of us in 1897.^ 



They were interpreted then as being formed at the expense 

 of the archoplasm, for the reason that in those cases where 

 they were present in the cone they were surrounded by an 

 area free from archoplasm, indicating that they arose by a 

 concentration of the archoplasm substance at that point. 



1 Foot, "The Origin of the Cleavage Centrosome," Journ. of Morph., vol. xii, 

 No. 3, 1897. 



