Katharine Foot and Ella Church Strobell 325 



5. Foot and Strobell. Photographs of the Egg of Allolobophora foetida 

 I. Journ. of Morph.. Vol. XVI, No. 3, 1900. 



6. Henneguy, L. F. Siir les rapjiorts des cils vibratiles avec les centro- 

 somes. Archives d'anatomie microscopique, Vol. I, 1898, p. 494. 



7. Kino, Helen Dean. The Maturation and Fertilization of the Egg of 

 Bufo lentiginosus. Journ. Morph., Vol. XVII, No. 2, 1901. 



8. VON Lenhossek, M. Untersuchungen iiber Spermatogenese. Arch. f. 

 mik. Anat., Bd. 51, Hft. 2, 1898. 



9. VON Lenhossek, M. Verhandl. der anatomischen Gesellschaft in Kiel. 

 1898, p. 117. 



10. LiLLiE, Frank U. The organization of the Egg of Unio, based on a 

 study of its Maturation, Fertilization and Cleavage. Journ. Morph., Vol. 

 XVII, No. 2, 1901. 



11. NiESSiNG, Carl. Die Betheiligung von Centralkorper und Sphare am 

 Aufbau des Samenfadens bei Saugethieren. Arch. f. mik. Anat., Bd. XL VIII, 

 Hft. I, 1896. 



12. Platner, Gustav. Beitrage zur Kenntniss der Zelle und ihren Theil- 

 ung. Arch. f. mik. Anat., Bd. XXXIil, Hft. II, 1889. 



EXPLANATION OF PLATE. 



The spermatozoa shown in this plate were collected at different times 

 from spermatojihores found in the slime tubes removed from copulating 

 worms. In each case one spermatophore was teased in a drop or two 

 of water, spread on a slide and dried In the air, or by heat from an 

 alcohol flame. The preparations were stained at once with iron haema- 

 toxylin and mounted in balsam.^ 



For the photos taken at magnifications of 1000 and 660 diameters, a 

 Zeiss apo. 2 mm., immers. lens, 140 apr., was used, with projection ocular 

 4, (diaphragm at 0) and camera draw demanded for each magnification. 

 For the photos taken at 450 diameters, the Zeiss apo. 4 mm., lens was used, 

 with projection ocular as above. 



For convenience we shall designate the three centrosome-like bodies, as 

 the apical granule, and the anterior and posterior granules of the middle- 

 piece. These granules are seen also in spermatozoa found in the sper- 

 mathecae, but the photo of these was overlooked in preparing the plate. 



In the half-tone plate some of the granules were strengthened slightly in 

 order to secure satisfactory printing. If any of our readers should wish 

 to compare the reproduction ^vith the original prints, the latter may be 

 obtained on request. 



Photo 1. Spermatozoon, showing spine, head, middle-piece, part of the 

 tail, and the three granules, one between the spine and head, one between 

 the head and middle-piece, and one between the middle-piece and tail. 

 Mag. 1000. 



^ Some of the slides were examined unstained, in glycerine, after five 

 hours' immersion in a saturate solution of osmic acid. The spermatozoa 

 failed to sho^v any osmophile granules. 



