82 



OEGANIC DEPENDENCE AND DISEASE 



living plant borers were chiefly green and blue-green algae, 

 only two of their species being recognized as having a prob- 

 able affinity with the fungi. In a very instructive paper by 

 Duerden^ on the effect of these algae in the disintegration 

 of recent corals, it is remarked that the red algae also have 

 now been recognized among these borers. 



V 



'q;^';. 



e d 



Fig. 67. Boring Plants (recent). a. Siphonocladus voluticola Hariot. x 80. 



h. Gonontiaf x 250. c. Gonontia polyrMza Bornet and Plahaut. x 250. 



d. Mastigocoleus testarum. x 330. (After Bornet and Flahaut, op. cit. ) 



That the debris of the Paleozoic beaches and the shallow 

 grounds of the sea, the living as well as the dead shells, 

 were abundantly attacked by these microscopic plant para- 



■i-Bul. Amer. Mus. Nat. Hist., v. 16, p. 328, pi. 32. 1902. 



