156 Miscellaneous. 



every point, except in that the embryonic cell of the male ovule 

 whilst retaining its cell-form, has become a special organ, endow^ed 

 with a special propert)^ viz. fecundation by the intromission of the 

 pollen-tube into the ovule : whilst in the female ovule, on the con- 

 trary, the embryonary cells analogous to those of the male ovule are 

 metamorphosed into anatomical elements (tracheae, dotted vessels, 

 cellular tissue, &c.)." 



The reporters go on to observe : — " 2. That the facts contained 

 in this part of the (R/I. Robin's) memoir demonstrate that, in cryp- 

 togamic plants, the antheridia must be regarded as the analogues of 

 the male ovides of vegetables : they are formed, in fact, of a homo- 

 geneous envelope, — the vitelline membrane, and contain a granular 

 mass, — the vitellus. At the expense of this vitellus are formed the 

 moveable animalcules of algae, mosses, &c., the true spermatozoa of 

 algse, as believed by MM. Thuret, Decaisne, and Montagne, &c. 

 The observations of M. Robin tend also to show, that the sperma- 

 tozoa of many algae have sometimes been confounded with spores 

 provided with vibratile cilia, or zoospores ; and he describes, after 

 some original observations, the development of those of Ulva lactuca. 

 He states that in this plant the granular contents, or vitellus of the 

 cells of the frond, — which fulfil the office of antheridia, or of the 

 male ovule, become broken up into two, four, or eight, or into as 

 many as twelve, twenty-four, and even thirty-two segments, or little 

 spheres, after the same plan as prevails in the division to form pollen 

 grains, or vegetable, or animal embryonic cells. Very soon four 

 cilia are developed on one point of the surface of these spherules, and 

 then the latter escape from the ruptured antheridium, evincing very 

 active movements. With respect to cryptogamic plants, the male 

 fecundating corpuscles of which are as yet undiscovered, further re- 

 searches are necessary. 



" 3. M. Reichert has watched the development of the spermatozoa 

 in the Strongylus aiiricularis , and in the Ascaris acuminata. In the 

 first stage, some transparent cells spring up at the bottom of the testi- 

 cular tubes, each provided with a germinal vesicle, the contentsof which 

 soon become granular, and assimilate it to the vitellus of the female 

 ovum ; whilst the envelope appears homogeneous and amorphous, like 

 the vitelline membrane : in short, it is a true ovule, similar in every 

 respect to one of known female origin. The vitellus very soon 

 divides into two spheres, then into four, each of which gets inclosed 

 by a wall, and constitutes an embryonic cell : by degrees each cell 

 thus produced changes its form, and at the same time a prolongation 

 makes its appearance at one of its poles, which forms the tail of the 

 spermatozoon, the cell itself forming the head or body. M. Segond 

 has, in conjunction with M. Robin, also noted this identity of the 

 male and female ovule in the blue Rhizostoma (Rkizostotna Cuvieri), 

 as well as some of the phsenomena of the evolution of the vitellus. 



"Resume. — 1 . It is seen that an ovule is formed in the male organs 

 analogous to that derived from the ovary ; that in the male ovule 

 grains of pollen or zoosperms are developed, after the same manner 

 as the primitive cells of the embryo, are formed in the female ovule, 

 and hence these fecundating corpuscles are the analogues of the era- 



