Edwards.] 216 [February 9, 



it with care when it arrives. Every spore may produce a different 

 variety, but it is not easy to understand that the same spore, or stipes, 

 can give rise to different varieties. As for the two species (G. con- 

 sirictum and capitatum) I have never been satisfied that they are dis- 

 tinct, and probably G. herculaneum is another variety." 



For my part, from the mode in which the two new valves are 

 formed within and between the two old ones, when self-division take3 

 place, I can readily understand how a great variation in both outline 

 and sculpture can occur. In this case the two forms have exactly the 

 same sculpture, and the difference between them merely lies in the' 

 outline of the valve. From my knowledge of how greatly this char- 

 acter varies in the Diatomacese, I, from an early period in my studies, 

 considered these two supposed species to be but forms of one, and this 

 discovery proves that my surmises were correct; at some future time 

 I may have something to say with regard to the genus Gomphonema, 

 and what, in my judgment, constitutes a species in it. I am now en- 

 gaged, and have been for some years, working up several genera, with 

 the express purpose of determining the true lines of specific distinc- 

 tion in them. And I must be permitted to here enter my earnest 

 protest against the custom which has become so wofully common, in 

 England more especially, of manufacturing species where they do not 

 exist. 



The labors of such self-supposed students of nature are more than 

 thrown away. Our books become crowded with worthless synonyms, 

 and this branch of biology has, in consequence, fallen into disrepute 

 among scientific observers generally. If those who have the oppor- 

 tunity of securing and examining specimens of Diatomaceae, would 

 only study them a little more carefully, and if they must publish, do 

 so only after properly maturing their knowledge, we might hope to 

 learn something of the life history of these strange atomies. Better 

 that really new species should forever remain unnamed, than that 

 such contributions, to the literature of the Diatomaceaa, as appear from 

 time to time in foreign journals, should ever see the light. It is a 

 curious fact that almost every one who becomes possessed of a micro- 

 scope of sufficiently high magnifying power, at once imagines that he 

 is abundantly armed and equipped, as well as qualified, to attack and 

 overcome the most difficult problems in biology. Hence we find the 

 most startling discoveries put forth by very immature observers of 

 nature who suppose themselves to be students, but who have really 

 given little time or thought to study. No branch of biology, perhaps, 



