A YORKSHIRE NATURALIST 115 



he introduced my specimens under the generic 

 name of " Williamsonia." But even yet my un- 

 happy memoir was not beyond the reach of trouble. 

 For economical reasons the officials of the Linnsean 

 Society left out of their plates some of the figures 

 which I had introduced into mine. This change 

 was forgotten when the proofs were corrected, the 

 result being that when I received my copies of the 

 memoir I discovered that the figures and letters of 

 reference on the plates and those in the text were 

 in hopeless disagreement. This was indeed a memoir 

 doomed to disaster. 



Similar objects to those described in it have since 

 been found in Sweden and India and other parts of 

 the globe, and are now included under the same 

 generic name. Opinions have varied as to the group 

 of plants in which the " Williamsonia " ought to be 

 placed, but at the present time (1894) the pendu- 

 lum, after swinging hither and thither, has returned 

 to my own original idea, that these objects are 

 Cycadean. 



But whilst the investigations here recorded were 

 in project a purely botanical question was also 

 engaging my attention. One of the most lovely of 

 the forms of aquatic life is the minute, fairy-like 

 sphere known as Volvox globator, familiar to all 

 microscopists. This object had been discovered by 

 Leeuwenhoek so far back as 1699, but for a century 

 and a half little, if any, addition had been made to our 

 knowledge of these elegant organisms, beyond what 



