460 On the Reproduction of the Cryptogamia. 



should be consulted in reference to the Conifera;, since so much new in- 

 terest now attaches to the facts revealed in them. 



Brown, R. On the Plurality and Development of the Embryos in the 

 Seeds of the Coniferse. Read before the British Association at Edin- 

 burgh, August 1834. Ann. des Sc. Nat. 2nd Ser. Bot. xx. 193; An- 

 nals of Nat. History, Ser. 1. xiii. 368. 



Mirbel and Spach. Notes sur l'embryogenie des Pinus Laricio et 

 sylvestris, &c. Ann. des Sc. Nat. 2nd Ser. Bot. vol. xx. 257- 



EXPLANATION OF PLATE XVII. 

 A. Hepaticce. 



Fig. 1. Jungermannia bicuspidata. An archegonium recently impregnated 

 (b), with another (a) unimpregnated. The first contains a rudi- 

 mentary fruit composed of two cells. In the inside of the perianth 

 inclosing the archegonia were found several moving spermato- 

 zoids; the arrows indicate the direction of the movements. (Hof- 

 meister.) 



Fig. 2. A rudimentary fruit extracted from a somewhat older archegonium 

 of the same plant. (Hofmeister.) 



B. Filices. 



Fig. 1 . Asplenium septentrionale. A vertical section of an archegonium, 

 just impregnated. {Hofmeister.) 



Fig. 2. Vertical section of the prothallium of the same plant, passing 

 through an embryo developed from the globular cell of the arche- 

 gonium ; the archegonium (a) is seen pushed aside by the enlarge- 

 ment of the embryo. (Hofmeister.) 



Fig. 3. Antheridia of Pteris aquilina : a, unopened ; b, just bursting ; 

 c, older one which has the walls of its cavity coloured brown. 

 (Thuret.) 



Fig. 4. Spermatozoids from Asplenium septentrionale. (Hofmeister.) 



C. Rhizocarpea. 



Fig. 1. Pilularia globulifera. Small spore. The inner coat, which has 

 become protruded through the fissiue of the outer coat, bursts 

 and discharges cellules, from some of which spermatozoids are 

 extricating themselves. (Hofmeister.) 



Fig. 2. The same plant. Vertical section of a prothallium with central 

 archegonium, just before impregnation. (Hofmeister.) 



Fig. 3. The same plant. Archegonium seen from above. (Hofmeister.) 



Fig. 4. The same plant. Vertical section of the prothallium with the em- 

 bryo in an advanced stage of development (a, archegonium). 

 (Hofmeister.) 



D. Lycopodiacea. 



Fig. 1. Selaginella Martensii. The inner coat of a large spore recently 

 discharged from the capsule, with the outer coat stripped off, so 

 as to show the young prothallium at the upper end. (Hofmeister.) 



Fig. 2. Selaginella denticulata. Vertical section of the prothallium and upper 

 half of a large spore, eleven months after sowing. Several arche- 

 gonia are seen, one of which exhibits a central cell. (Hofmeister.) 



Fig. 3. An archegonium of Selaginella Martensii. (Hofmeister.) 



Fig. 4. An archegonium of Selaginella denticulata just impregnated, the 

 central cell divided into two by a cross wall. (Hofmeister.) 



Fig. 5. An archegonium seen from above. (Hofmeister.) 



