70 NATURAL SCIENCE. January. 



U. subconstricta. J. de C. Sowerby in 1840 described U . robusta Gecl. Coalbrookdale. 

 In 1844, Prof. King proposed the name " Anthracosia for a group of Unionidae 

 characteristic of the coal measures" without figures or description as the reviewer 

 says a preliminary notice of the worst sort. In Dec. 1855 M'Coy published the 3rd 

 fasciculus of his work on the Synopsis of the Classification of British palaeozoic 

 rocks with a Diagnosis of Carbonicola to which genus he referred the U. acutus, 

 U. subconstricta, and U. robusta, of the Sowerbys and U. turgeda. Brown. A 

 mistake was made in describing the genus as possessing a posterior lateral tooth. 

 King on receiving a copy of this work immediately published in Jany 1855 (Ann. 

 Mag. Nat Hist 1856) a description of Anthracosia and in a postscript dated Dec. 27, 

 1855, says, " My friend evidently thinks it synonymous with Anthracosia which he 

 admits being aware I intended describing ; However, if the genus Carbonicola possess 

 the characters diagnosed by Prof. M'Coy, it is clearly not the same as my Anthracosia 

 which does not possess lateral teeth." There can thus be no doubt as to the priority 

 of Carbonicola for one mistaken character in a description cannot invalidate, but 

 the reviewer drawing on his own fertile imagination says " M'Coy failed to under- 

 stand the genus he described and his diagnosis could only have been drawn up from 

 specimens of other genera from a younger formation." His accusation is completely 

 wrong for M'Coy correctly referred the four species mentioned above quite correctly 

 to his genus, where as King described a new specific type and only referred one of 

 Brown's many forms to his genus. It turns out too that the form of hinge described 

 by King obtains only in the species of C. aquilina, another of J. de C. Sowerby's 

 types. I did suggest that the lateral tooth was inferred from the close affinity 

 Carbonicola has to Unio, but there is not the slightest foundation for the reviewer's 

 statement ; as it will appear later, the reviewer knew of this change and the reasons 

 for it long before the work was in type and he wrote me that though he regretted 

 the change, it seemed to be enevitable. 



My reviewer seems very troubled that species and varieties are not defined with, 

 mathematical accuracy. This is of course the resultant of his long application to 

 museum work, but he would go further for in a letter dated Nov. 20, 96, he writes 

 me " Your definition of species is very faulty but for this I blame the Palaeonto- 

 graphical. They should establish a set of rules for the guidance of workers so that 

 all who consult their publications may know what view is taken of specific distinc- 

 tion as a whole. As it is each man is a law unto himself and the modern palaeonto- 

 logist stands on one side and scoffs." It is what I imagine even you. Sir, would call 

 " high falutin," but it argues the possession of a mind more adapted to mathematical 

 formulae than to Biology. On one hand, he demands mathematically defined species 

 and on the other, grumbles that the way species seem to pass into each other is not 

 better shown. 



Another point objected to is the invention of species on one or two examples, 

 and I cordially agree with him, but this is a matter of personal observation and it is 

 the easiest and cheapest form of criticism to judge work in the absence of speci- 

 mens. It is at times necessary to describe unique examples, but it should be done 

 with great caution. In two of the cases the reviewer will be glad to learn that other 

 specimens have turned up which I think justify my views. In the case of the 

 figures of Anthracomya dolobrata the reviewer objects that the type differs from the 

 other shells referred to the species. Here he is not making allowance for the 

 imperfections of the type and consequently his arguments are valueless. He also 

 suggests that C. subconstricta is the internal cast of C. robusta, but he has not 

 noticed that Sowerby's type is a testiferous example. Several of the other figures of 

 this species are those from which M'Coy redescribed this species and are in the 

 Woodwardian collection Cambridge. One more example of the reviewer's methods 

 will suffice. He says " the specimens 6 & 7 PI ix. are taken as types of C. aquilina, 

 but they might equally serve as elongated forms of C. acuta." It is evident to me 

 that he has not yet arrived at the fundamental differences between my descriptions of 

 these two species, but it so happens that the two shells in question were brought to 

 my house by the reviewer himself and that it was largely on his suggestion that they 

 were referred to C. aquilina. Reviewers should really be careful in little trans- 

 actions of this kind or the value of their remarks is liable to be heavily discounted. 



