i6o NATURAL SCIENCE. Feb.. 1894. 



have not mentioned, I respond to your request for additions by sending them 



herewith. 



Autoteninon (avTO s, self ; Tefxvoi, I divide), a single free Protozoon, so called in 



allusion to the common mode of multiplication, and in distinction to zoon which 



is the unit of the Metazoa. 

 Epembryonic (eTt, after; e /J-p pvov, embryo), a term characterising all stages of 



ontogeny after the embryonic. 

 Mnemegenesis was less correctly Mnemogenesis in the original paper. 

 Tachvgenesis (t o. x v s , quick ; yei'ecrts~, formation or development), the phenomenon 



previously known as "acceleration of development." 

 Tachygenetic, adjectival form of preceding, applied to normal types in which accelera- 

 tion of development occurs. 



It may also be noted that Kinetogeny of Ryder is merely a variant of Kinetogenesis 

 of Cope, with the same meaning and corrupt etymology, only more so. Some people 

 are never satisfied. 



You are doubtless correct in criticising Cotype ; for typus, though used by the 

 Romans just as type is by us, was always regarded by them as a Greek word and they 

 would certainly have used the prefix syn-. At the same time Oldfield Thomas is not 

 altogether to blame, since he gives the credit (or discredit) for the word to C. O. 

 Waterhouse, and merely retains for himself the credit of defining it more exactly. 



Although one of those who have before now fallen under the lash of your 

 criticism in respect of word-making, permit me to say that with this your last article 

 I fully agree, and especially with the last paragraph of it which relates to the popu- 

 larising of science. After reading the article that preceded it, I dreamed all night 

 that I was a sorus of plurilocular sporangia and Laminarian paraphyses rolled up in 

 a Fucaceous conceptacle to protect me from the attacks of oogonia, antheridia and 

 filamentous cryptostomata. 



F. A. Bather. 



FONA OR FUDDLEITE. A NeW MINERAL. 



A GOOD-NATURED friend has just drawn my attention to the note under this 

 heading which appears in your last issue. 



Mrs. French- Sheldon was kind enough to send me a copy of her interesting 

 work, and, like your contributor, I was somewhat amused at, and for a momeut 

 exercised to understand, the extraordinary collocation of symbols which is there 

 made to do duty for the formula of Trona, which, in my letter to the fair authoress, 

 I had represented — or perhaps I had better say, attempted to represent — as 



2 Na.,0 3 CO., 4 H2O. 

 The matter, I think, is hardly worth the space it occupies in a periodical of the 

 dignity and importance of Natural Science ; but, in justice to the lady, may I 

 suggest to your contributor, whose acumen would seem to lag behind his sense of 

 humour, that he might exercise, and possibly even improve, his critical Jlair by 

 ascertaining, cnvrente calamo, how this expression could be calligraphically trans- 

 formed into something akin to that which has so greatly puzzled and disturbed 

 him. 



T. E Thorpe. 



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