79 



apertures. Rarely three apertures without grooves, as in 

 Morina persica. A number of peculiar forms are here fully 

 described which had partly been previously published. Some 

 cases are also mentioned where all the grooves are not provi- 

 ded with apertures, yet in this case the pierced grooves stand 

 in a definite proportion to the unpierced. 



Lastly, there are forms with a cellular (?) texture of the 

 outer pollen membrane ; in some cases only a part of these 

 fields which have the cellular appearance are provided with 

 apertures, as in Phlox ; in others, on the contrary, all the 

 fields have apertures, as in Gomphrena globosa. 



3. Pollen grains with three tunics. Where a greater 

 number of tunics exist than in the second division, the addi- 

 tional ones must not be regarded as new tunics, but duplica- 

 tions either of one or the other. In the pollen of the Coniferte 

 the inner tunic is doubled, in the Onagrece the outer one ; nay, 

 M. Fritzsche alleges that he has observed a duplication of the 

 inner tunic in Clarkia elegans. (If the pollen of Pinus, Larix, 

 TaxuSy and Juniperus, be observed comparatively in this re- 

 spect, we may easily be convinced that no reason exists for the 

 admission of such duplications. Rep.} 



4. Pollen grains with four tunics. Clarkia elegans, spe- 

 cies of CEnothera and Encharidium concinnum are here enu- 

 merated. 



I have published some observations on the Spermatozoa of 

 Jungermanniae*, which exactly resemble those described by 

 M. Unger in the anthers of the genus Sphagnum. I noticed 

 the occurrence of these Spermatozoa of the Jungermannia in 

 the interior of lenticular compressed vesicles (ceUs ?) ; in 

 each vesicle there was a single worm-like creature with thick 

 cephalic extremity and thin tail, and situated quite at the 

 margin of the vesicle, so that the filiform tail can run round the 

 margin of the entire vesicle and again touch the head. These 

 cells containing the Spermatozoa are very large and in great 

 quantity in the anthers ; and in some genera of mosses they 

 are enveloped in gelatinous mucus, which swells by absorp- 

 tion of water, causes the anther to open and expels the whole 

 mass from it. On the solution of the gelatine in water these 



Wiegmann's Archiv, 1837, i. p. 430. 



