1897] "71 



CORRESPONDENCE 



OCEANIC ICHTHYOLOGY 



The reviewer of Goode and Bean's "Oceanic Ichthyology" (Natural Science, vol. x., 

 pp. 338-340) has made a gratuitous assumption, which devolves on me unmerited credit 

 and responsibility. 



The reviewer says "it is to be noted that the literary part of the work bears signs 

 of having been intrusted to a third author not under proper control of the two 

 responsible authors." The "third author" is evidently myself. I feel compelled to 

 deny either credit or responsibility for all that is not specifically accredited to me. Dr 

 Goode devoted much time and thought to the keys, and I had nothing to do with the 

 original compilation. 



The specific information that certain fishes have and others have not a mesocora- 

 coid, so far as the italicised portions credited to me are concerned, I am responsible for, 

 but not entirely for their application. 



The critic remarks, "as a matter of fact, the vast majority of the fishes placed 

 here have not been examined with reference to this point. " True ; but enough have 

 been examined to authorise the deduction formulated. The same argument might be 

 adduced against other generalisations. . . . 



As to the definition of Pterothrissidae, it will be evident from the context that the 

 mistake is due to unintentional repetition instead of the requisite antithesis. The 

 family Alepocephalidae is defined as having the "dorsal fin similar and opposite anal," 

 and the Pterothrissidae should have been contrasted as having the dorsal fin unlike, 

 and longer than anal. Undoubtedly carelessness and oversight are manifest, and I am 

 willing to assume that I glanced over the proof and therefore to share the blame, but I 

 had nothing to do with the original manuscript. Drs Goode and Bean, as well as my- 

 self, had much on hand, and doubtless the proof sheets were often read in a perfunctory 

 manner. But in this respect, we have good company. . . . 



Such mistakes unfortunately are too common and are generally designated as 

 " slips of the pen " or " lapsus calami." I do not defend them, but it does not become 

 the guilty to animadvert on them too strongly. . . . 



What are or what are not family characters, is a question about which Dr Giinther 

 and I have long differed, and I wish neither to defend my view nor to attack those of 

 others on this occasion. All the many American naturalists, at least, agree with me on 

 such points. Other strictures I leave to the surviving of the authors, if he should deem 

 them worthy of attention. 



Some notice of the remarkable novelties obtained since the publication of the 

 results of the Challenger Expedition might have been given by the reviewer, but I 

 shall not trespass further on your space to do so. Theo. Gill. 



[We regret that Dr Gill should assume our review of Goode and Bean's ' ' Oceanic 

 Ichthyology " to have been written or inspired by Dr Giinther, who had no share what- 

 ever in its preparation. Like many unsigned reviews in Natural Science, it was the 

 work of more than one author, and expressed the views of the editorial management of 

 this journal, not those of any one individual. We have therefore omitted from Dr 

 Gill's lettter some remarks on Dr Giinther 's works.— Ed. Nat. Sci.] 



Slugs 



I have recently received from an American malacologist a communication, in which 

 he says that in a paper,* written in conjunction with Lieut. -Col. H. H. Godwin-Austen, 

 I have "wrongly applied the term slug by using it for such genera as Parmarion, 

 Microparmarion, &c." 



It is very largely a question of individual opinion as to what genera should be 

 included under this term, but I fail to see any reason why Parmarion and its allies 

 should not be termed slugs. 



The slugs are not a group by themselves which can be separated into distinct 

 families apart from the rest of the Pulmonata. On the other hand, very many genera 

 are closely related to genera in which there is a conspicuous shell. In the above- 

 mentioned paper the same opinion was expressed as follows :— " We think that future 



* Proc. Zool. Sec, 1895, p. 249. 



