Correspondence. 387 
Mr. Miller has promised on some future occasion to " make known 
the motives that actuated the unwarranted attack, as I recognize the 
author as well by his feet tracks, as I would if his signature had ap- 
peared with the middle name at full length as usual.' 
It is well known to those who are acquainted with Crinoid literature, 
that this passage refers to me. But Mr. Miller is entirely mistaken ; 
for I neither wrote the review in question, nor did I know anything 
about it till some time after its publication. 
As, however, Mr. Miller imagined me to be the author of it, the in- 
temperate violence of his personal attact upon me in the November and 
December numbers of the American Geologist may be readily under- 
stood. We have unfortunately differed upon a small point of nomen- 
clature, Mr. Miller preferring the empirical, and I the rational termin- 
ology. The latter is in general use in Europe and Australia ; and 
it has been gradually adopted in America by Messrs. Wachsmuth and 
Springer, A. G. Wetherby, H. S. Williams, C. D. Walcott, A. H. 
Worthen, W. R. Billings, E. N. S. Ringueberg, J. F. Whiteaves and 
A. Agassiz. I am not aware that any American palaeontologists have 
used the old and purely empirical nomenclature during the last eight 
years, with the exception of Mr. Miller and his collaborator, Mr. Gur- 
ley, who are, therefore, in a somewhat isolated position ; and this may 
perhaps account for the tone of Mr. Miller's remarks upon the subject 
in pages 279-281 of your November number. Among these remarks 
there is one statement which is so absolutely untrue that I must ask 
you to allow me to contradict it. According to Mr. Miller, I have said 
that the so-called subradial plates of palseocrinoids are "the genital 
plates," an assertion which he calls " purely gratuitous, and not war- 
ranted by any of the known facts relating to crinoids." This criticism 
was not necessary, as the assertion in question was never made. But 
like many other morphologists and palaeontologists I have described the 
so-called subradial plates of crinoids as homologous with the so-called 
genital plates of urchins ; and this may perhaps account for Mr. Miller's 
very incorrect reference to the subject. It is useless, however, to look 
for a proper understanding of the morpholgical questions which are 
here involved, or even of the meaning of the word "homologous," on 
the part of an author whose zoological knowledge is so limited that he 
tells his readers that the sponges " are not to be regarded as any more 
highly organized than the Rhizopoda." 
Mr. Miller's acquintance with recent publictions on the subject of the 
Crinoidea is equally defective. On page 356 of your December number 
he quotes against me an opinion of Wachsmuth and Springer's to the 
effect that they do not understand how the five summit plates of Haplo- 
erinus can represent the orals of a palaeocrinoid ; and he briefly adds, 
" Neither does any other one." 
It is a pity that Mr. Miller should have committed himself to such a 
very positive statement ; for it is not true. If he will consult the well 
known text books on paheontology by Zittcl, Hoernes, Steinmann, and 
Nicholson, and also Neumayr's important work "Die Stamme des 
