Archive image from page 512 of The cyclopædia of anatomy and. The cyclopædia of anatomy and physiology cyclopdiaofana0401todd Year: 1847 SEMEN. 491 itself, and then becomes a short, and gene- rally curved, cylinder (B), one end of which Fig. 372. BCD Seminal cells in the testicles of Clubiona claustraria. is frequently club-shaped. The nucleus at the same time generally urges itself to- wards the outside, its point penetrating through the external cellular membrane. The projecting part of the nucleus generally ap- pears like a protuberance at the margin of the cell, the greater part of it
Archive image from page 512 of The cyclopædia of anatomy and. The cyclopædia of anatomy and physiology cyclopdiaofana0401todd Year: 1847 SEMEN. 491 itself, and then becomes a short, and gene- rally curved, cylinder (B), one end of which Fig. 372. BCD Seminal cells in the testicles of Clubiona claustraria. is frequently club-shaped. The nucleus at the same time generally urges itself to- wards the outside, its point penetrating through the external cellular membrane. The projecting part of the nucleus generally ap- pears like a protuberance at the margin of the cell, the greater part of it being still situ- ated in the interior (c, D). In some cases, however, it breaks forth in its whole length (E). It then looks like a peduncle-shaped appendix. We have not been able to discover further stages of develope- F/s. 373. ment in the interior of the testicles ; but we have suc- ceeded in detecting, besides the already mentioned cor- puscles, a number of dis- tinct linear fibres of -fa'' — aV' (J- 373.) in the spoon- shaped capsules on the pal- pi of the males, which, no doubt, were developed sper- matozoa. The anterior half of these was generally bent in an arched cylindrical form, and thicker than the pos- terior tail-like part. Very similar, only rather longer, Seminal fibres of seminal fibres are likewise Clubiona. found in the seminal capsules of the palpi in a species of Tetragnathus. It can hardly be doubted that these fibres have originated from the previously described spermatic cells. The changes of form to which the nucleus is subjected in the course of developement present a gradual approximation to this form of spermatozoa, at least to the form of the anterior thick- ened corpuscles, with which the nucleus moreover corresponds in its physical cha- racters. In order to render the metamor- phosis of the nucleus into spermatozoa com- plete, it certainly is necessary that the external cellular wall should disappear; but this is a general rule in the develop
Size: 2805px × 713px
Photo credit: © Actep Burstov / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: 1840, 1847, anatomy, archive, book, bookauthor, bookdecade, bookpublisher, booksponsor, booksubject, bookyear, drawing, historical, history, illustration, image, london_sherwood_gilbert_and_piper, mblwhoi_library, page, physiology, picture, print, reference, todd_robert_bentley_1809_1860, vintage, zimmermann_a_albrecht_b_1860, zoology
