THE AMERICAN 



MONTHLY 



MICROSCOPICAL JOURNAL. 



Vol. XII. JUNE, 1891. No. 6. 



.{11 co)nmii)iicationsfor this Journal, wliethcr relating to business or to editorial 

 matters, and all books, pamphlets, exchanges, etc., should be addressed to Ameri- 

 can Monthly Microscopical Journal, IVashingtofi, D. C. 



■ European subscriptions may be sent directly to the above address accompanied 

 by International Postal Order Jor $1.13 per annum, or they may be sent to Messrs. 

 Triibner &> Co., 57 Ludgate Hill, London, or to Mr. W. P. Collins, ijy Great 

 Portland street, London, accompanied by the yearly price oj Jive shillings. 



Diatoms: Their Life History and their Classification. 



By Rev. FRED'K B. CARTER, 



MONTCLAIK, N. J. 



[With Frontispiece.] 

 {^Continued from page loi.') 



It is not claimed that the points mentioned will always be sufficient, 

 but they will in many cases, especially when studied with the help of 

 the figures of the fresh-water and fossil forms, and the beginner will be 

 able to make enough progress to spur him on to identify, by closer study 

 and the use of more elaborate keys, such forms as puzzle him ; whereas, 

 at first, such a key, especially if it included all the genera, fresh-water, 

 fossil, and marine, might frighten him, and possibly make him 

 think it too much trouble to attempt the classification at all. For the 

 drawings, I am indebted to the kindness of Mr. Robert W. Smiley, who 

 performed a like service for me in connection with my paper on the 

 Desmids, and I wish to express my thanks to him here. After the 

 student has made himself familiar with the fresh-water and fossil forms, 

 if not before, he will surely want to own a copy of Wolle's fine work 

 on the Diatomaceae of North America (if he can possibly do so I would 

 advise his obtaining it at once, as the number of copies is limited), and 

 I add here a list of references to his illustrations of the marine forms 

 just rtientioned : 



List of Figures in thb Fkontispibce. 



Fig. 30. Synedra fulgens. Fig. 41. Coscinodiscus argus. 



31. (Joniothecium Rogersii. 42. Arachnoidiscus Ehrenbergii, var. Cali- 



33. Hercotheca mammillaris. fornica. 



33. Blblaritim ellipticuni. 43. Actiiioptychus (Omphalopelta) areola- 



34. Biblariiim tStylobiblium) clypcns. lus. 



35. Peiiptera tetracladia. 44. ActinoptyLhus undulatus. 



36. Dicladia caprcolus. 45. Actinocyclus Ehrenbergii. 



37. Hemiaulus bifrons. 46. Heliopclta nitida. 



38. Eupodiscus argus 47. Asterolampra rotula. 



;9. Auliscu.s Grunowii. var. Californica. 48. Asterolampra (Asteromphalos) Hiltoni- 



40. Systephania raeana. ana. 



Copyright, 1891, by C. W. Smiley. 



