324 Mr. S. S. Buckman on 



Tlie conclusion arrived at is that Cletotliyr is cannot ha used 

 on King's autliority at all, and if it be used on PliiHij)s's 

 foundation it takes ))riority of Ath/ris. ]\I'Coy, indeed, 

 admits as much when he says of Athyris (p. 146) : — " Prof. 

 Phillips is the only author wlio has recognized the group ; he 

 forms of it his last division of the genus t^infera." 

 Pliillips^s last division of the " Delthyridaj or Spirifers" — 

 M'Coj uses this phrase — is Cle'iothyru (Pal. Foss. p. 55). 



As IJypothyris cannot be used for the Atrypa {Rhyn- 

 clionella) cuhoides series — first because it does not belong 

 there, and second because it has been preoccupied, — it becomes 

 necessary to name afresh. It is desirable to make as little 

 change as possible, so there may be suggested 



Genus IIypothyridina, nom. no v. 



Genotj'pe Atrj/pa cuhoides, Sowerby, = Hypothyris, King, Hall & 

 Clarke, Schuchert et al. (non Phillips). 



As Cleiothyris is not available on King's autliority, and as 

 it seems to be generally agreed that the A. Royssii scxitB 

 requires a separate name from A. concentrica, then a new 

 term must be used : 



Genus Cleiothyeidina, nom. no v. 



Genotype AtJiyris Hoyssii, Davidson, Mon. Garb. Brach. pi. xviii. fig. 8. 

 Syn. Cleiothyris, King et auctt. (non Phillips). 



COMPOSITA, SeMIXULA. 



The first of these generic designations has been entirely 

 overlooked, yet it must be confessed that its author, Capt. 

 Thomas Brown, has done his work much more accurately 

 than his ))rofessorial contemporaries; he, at any rate, has 

 definitely fixed and described his type thus: — "Genus Com- 

 2:)0sita, Brown. Shell somewhat pentangular ; hinge-line very 

 short ; beak of the larger valve produced, with a small 

 circular perforation ; inside furnished with si)iral apjiendage.'^. 



" This genus is founded upon the ISpirifer anibiguiis of 

 Sowerby and is intermediate between that genus and Tere- 

 hrahda. 'J'he ])erf'orated beak removes it from Spirifer, and 

 the internal spiral a)i))end;igcs never exist in the genus Tere- 

 hratula, but are peculiar to the geim-? Spirifer. 1. Composite 

 amhigua, Spirifer amhiguus, Sowerby " *. 



The date is given by Mr. C. Davios Sherborn in a 

 pamphlet, " Conch. Writings of Capt. Thomas Brown," Proc. 



* Brown lilust. Foss. Conch. Gt. Britain and Trehmd, p. 131 (1845). 



