

















• 























■ 



1 



















■ 









POSITION OF TUB DICTYOTACE2E. 467 



diclotoma spread out in the water in the form of hyaline globules 

 like the spermatia which escape from the antheridia in the 

 Moridea, and they seem, like them, non-motile." The male 

 corpuscles of Dictyopteris polypodioides are not spherical, gene- 

 rally pear-shaped, sometimes irregular in outline, and consist of 

 well-marked granular, not homogeneous, protoplasm, being dif- 

 ierent from the spermatia of Floridea, as quite recently more 

 accurately described by L. Guignard * On one occasion, between 

 w and 11 in the evening, I was examining the antheridia micro- 

 scopically, when I saw one from which the male corpuscles were 

 escaping and exhibiting movements of such a nature as to give me 

 the impression that they were ciliated. Subsequent examina- 

 tion, again and again repeated in different ways (and with a 

 rrBHtt. immersion-objective), of preserved material has strength* 

 my conviction that the male corpuscles of Dictyopteris are 

 aot polliuoids, like those of the Florideae, but antherozoids, essen- 

 tially like those of Outlet nacea and Fucacea. Fig. 10, pi. v., 

 ^presenting a developing antherozoid of Fucus vesicuhsus in 

 Guignard's paper already quoted t, is very like stages I have 

 Peen m the developing male corpuscle of Dictyopteris. Still I 

 must ask to be permitted to reserve a final expression of opinion 

 °o the presence of cilia until I have made a detailed examination 









ened 



of fresh 



material $. 



May 



ii. Oogonia. 



are in sori, they 



Jf e "* Dictyopteris and Spatoglossum most generally isolated ? 



sorus 



°f Dictyota as the homologue of the Floridean cystocarp. Spite 

 ®any attempts, no one has observed any signs of a pro- 



sorus 













Cognizable condition from superficial cells of the thallus. 



a * ^ G «"'gnard, "Developpement et Constitution des Antherozoides " (Bevue 



U ^ de Bot. i. (1889), no. 4. 



I i* Gu ignard, in Revue Gen. de Bot. i. (1889), no. 3. 



? l mu8t offer as an excuse for the incompleteness of ray observations on this 



J°*t that the grant from the Boyal Society waa made to enable me to carry 



2 mTe8ti gat»ons on the Florid*,, and I did not feel justified in spending much 



"J* on the Phaophycea, but contented myself with preserving the material for 



""baeQuent examination. 

























































H 



































■ 





- 



I 



' 



- 





^ 











. 



' 







. 





. 



i 



I 





