134 
J. T. CUNNINGHAM. 
further light on the inner meaning of reproduction, the most 
mysterious and most distinctive phenomenon of life. 
EXPLANATION OF PLATE X, 
Illustrating Mr. Cunningham's report on “Van Beneden’s 
Researches on the Maturation and Fecundation of the 
Ovum.” 
List of reference letters. 
a. p. Accessory portion of germinal vesicle, c. z. Cortical layer of vitellus. 
dth. Deuterhyalosoma. h. d. Homogeneous droplets of vitellus. h. s. Hya- 
line spheres of vitellus. p. d. Polar disc. p. g. First polar globule, p. g'. 
Second polar globule. p. i. Plug of impregnation, pth. Prothyalosoma. 
r. sp. Refringent body of spermatozoon, r. g. Refringent granules of vitellus. 
s. n. Secondary nucleus of germinal vesicle, sp. Spermatozoon. 
Fig. 1. — Ovum before the entrance of the spermatozoon. Osmic acid, 
picro-carmine. Obj. 8 , Hartnack. (V. B., PI. X, fig. 5.) 
Fig. 2. — Deformation of the germinal vesicle at the time of the penetra- 
tion of spermatozoon. Alcohol, borax-carmine. Obj. 8 , Hartnack. (V. B., 
PI. XIY, fig. 10.) 
Fig. 3. — Spermatozoon in the uterus, conoid stage. Obj. 8 , Hartnack. 
(V. B„ PI. XI, fig. 14.) 
Fig. 4. — Ypsiliform figure. Nitric acid, borax-carmine. Obj. ^th, Zeiss. 
(V. B., PI. XV, fig. 3.) 
Fig. 5. — Expulsion of first polar globule. Nitric acid, borax-carmine. 
Obj. j^th, Zeiss. (V. B., PI. XVI, fig. 17.) 
Fig. 6 . — Second pseudokaryokinetic figure. Nitric acid. Obj. ^th, Zeiss. 
(V. B., PI. XVII, fig. 12.) 
Fig. 7. — Later stage of same. Alcohol. (V. B., PI. XVIII bis, fig. 1.) 
Fig. 8 . — Formation of second polar globule. Alcohol. (V. B., PI. XVIII 
bis, fig. 3.) 
Pig. 9 . — The two pronuclei. Alcohol, borax-carmine. Obj. -j^-th, Zeiss. 
(V.B., PI. XIX bis, fig. 9.) 
Fig. 10. — Longitudinal division of chromatic loops in first segmentation. 
Alcohol, borax-carmine. Obj. d, Zeiss. (V. B., PI. XIX bis, fig. 25.) 
