1908] BRIEFER ARTICLES 411 



The antherozoids measure 41 ft across when free. They are thus about 

 two-thirds the size of those of Microcycas, which appear from Caldwell's 

 drawings {loc. cit.) to measure 60/i across. Again, they are but one-sixth 

 the size of those of Zamia as figured by Webber, s 



That the antherozoids should be of smaller size than those of recent 

 cycads is explicable when one considers the primitive nature of Lyginoden- 

 dron and how many fern characteristics it retained. Moreover, there is 

 considerable probability that the number of antherozoids produced by one 

 pollen grain was not limited to two, although there is no evidence as to 

 how many were produced. It is obvious, however, that this pteridosperm 

 did not produce as many as Caldwell has shown is the case with :Micro- 



cycas. 



figure {fig 



bounded by a thin wall of elongated cells of nucellar origin (jiw), and that 

 the tongue of nucellar tissue characteristic of the Lagenostoma type of 

 ovule is cut obliquely at nl. Within the space thus delimited lie the remains 

 of four pollen grains {p\ p', p\ p^). Of these p^ still contains one an- 

 therozoid, and shows but little protrusion of endospore. The grain p^ is 

 empty; its epispore shows thin areolae, and at e the endospore has pro- 

 truded and shows very faintly one hexagonal cell still preser\'ed near its 

 base. The grain p^, at the bottom of the exposed part of the pollen chamber, 

 shows clearly five hexagonal cells (/), each with a central black spot. The 

 grain has been injured and its contents cannot be determined. Between 

 the grains p^ and p^ lies one of the bodies I interpret as antherozoids. The 

 hyaline area of this body appears to correspond with the apex of the coil, 



but cilia cannot be demonstrated. 



A similar body appears on the right near the upper part of the pollen 

 Chamber, and this also shows a hyaUne area. Accompanying this gamete 

 are the problematical cells which apparently form a continuous tissue and 

 therefore are not chytridiaceous. There are no fungal hyphae connected 

 with them and each cell contains a minute central body. Not far off lies 

 part of a fourth antherozoid {fig- 2, «0, which has evidently been cut across 

 in the process of making the slide. 



CONCLUSION 



That such bodies as pteridospermous antherozoids should be preserved 



rocks 



In 



to those who are familiar with the results of palaeobotanical research. 



5 Webber, H. J., Spermatogenesis and fecundation of Zamia. U. S. Dep. Agric, 

 Bur. PL Ind., BuU. 2. pp. 100. ph. 7. 1901- 



