186 PjaOCEEDINGS OF THE MALACOLOGICAL SOCIEir. 



A careful examination of the Mitra shows that it is certainly distinct 

 from M. interlirata, and that it possesses all the features of M. circidata 

 of Kiener. The distant spirals and the intervening sculpture are precisely- 

 similar, and the number of the columellar folds is the same, namely, three 

 and a very faint anterior fourth, whilst in interlirata there are five with 

 the indication of a sixth. 



As this remarkable instance of boring is likely to be referred to in 

 future works, it seemed to me advisable to make the above corrections as 

 soon as possible. E. A. Smith. 



Note on the Dates of Publication of the various parts of 

 Moquin-Tandon's " Histoire naturelle des Mollusques terrestres 

 ET fluviatiles de France." {Read 9th December, 1904.)— In the Pro- 

 ceedings of the Malacological Society, vol. v, p. 261, Mr. B. B, Woodward, 

 on the authority of the " Bibliographie de la France," gives the dates 

 upon which the various component parts of this important work were 

 published. The particulars there given would appear to be inaccurate, 

 as MM. Letourneux & Bourguignat (Prodr. Malac. Tunisie, 1887, p. 1, 

 note), who investigated the subject, give eai'lier dates for every individual 

 part. According to these authors the true dates of publication were : — 



Livr. I, issued April 12th, 1855. 

 „ II „ May 4th, 1855. 

 „ III „ August 1st, 1855. 

 „ IV „ September 10th, 1855. 

 ,, V „ January 2nd, 1856. 

 „ VI „ April 9th, 1856. 



J. W. Taylor. 



Note on Geitodoris planata (Alder & Hancock). {Read 

 12th January, 1905.) — Since I wrote my paper in this journal (vol. vi, 

 p. 180) to prove that Alder & Hancock's Doris planata should bear this 

 name, my attention has been called to tlie account of the species in 

 Jeffrey's British Conchology, vol. v, p. 85, written by Alder, as stated on 

 p. 27. It says : " The examination of further specimens of different sizes, 

 from the Clyde district, proves that the D. planata of the ' British 

 Nudibranchiate Mollusca' is the young of D. testvdiriaria. In its young 

 state it is extremely flat, and the gills imperfectly developed." Alder's 

 c%uthority on such a point must naturally carry great weight, but it is 

 noticeable that, whereas he says he had seen further specimens from the 

 Clyde, he does not say that he had seen any from the Mediterranean, and 

 merely refers to Risso (Hist. Nat. I'Eur. Mer., vol. iv, p. 33, fig. 15). 

 It is therefore probable that he identified the specimens with D. testudi- 

 naria merely on the strength of Risso's description, and, if that is so, 

 1 do not think the identification can be considered certain, for he can have 

 had no means of comparing the buccal parts, of which Risso makes no 

 mention. But these organs, which are clearly referred to by Alder & 

 Hancock (Brit. Nud. Moll., pt. vii, p. 42), are the most important 

 characters of D. jdanata, and distinguish it from all other recorded British 

 forms. Until it is shown that the D. testudinaria of the Mediterranean 

 possesses them, I think the specific name planata should be maintained 

 tor the British form, and the genus seems to me undoubtedly Geitodoris. 

 Risso's D. testudinaria has been identified by Bergh and others with 

 Platydoris argo, but this identification also is not certain, as Risso's 

 description and figure are unsatisfactory and inadequate. The external 

 characters are not in any way remarkable, and might apply to many 

 Dorids, except that the animal is described and depicted as having 



