172 MR. A. G. BUTLER ON THE GENERA [Feb. 4, 



One specimen of this species, as well as of P. plicifera, was ob- 

 tained by Dr. Meyer at Laguna del Bay. 



millims. 



Total length 32 



Fore limb 20 



Hind limb 60 



Distance between vent and heel 33 



Fourth toe 17 



4. A Monographic Revision of the Genera Zephronia and 

 Sphcerotherium, with Descriptions of new Species. By 

 Arthur G. Butler, F.L.S., F.Z.S., &c. 



[Received December 11, 1872.] 

 (Plate XIX.) 



In the * Annals and Magazine of Natural History ' for last 

 November, I added eighteen species to these two genera. Subse- 

 quently I have been favoured by Mr. Wilson Saunders with a sight 

 of his collection, in which I have discovered two new Sphcerotheriu ; 

 whilst a recent examination of the Banksian Collection in the British 

 Museum has brought to light two examples of a fine new Zephronia. 



As I have had some little difficulty in determining the species of 

 these two genera, owing to their great similarity one to another, I 

 have thought that it would facilitate the study of the group if I were 

 to draw up a synonymic list of the described species, grouping them 

 into sections founded upon well-marked structural characters. 



In the case of some of Brandt's species (the original descriptions 

 of which I have hitherto sought for in vain under the guidance of 

 the references given in Gervais's ' Apteres '), I have given trans- 

 lations of the diagnoses as cited by M. Gervais. This I have, how- 

 ever, only done either when the species described is unknown to me, 

 or when certain characters mentioned by the author indicate to which 

 of my sections the species belougs. I have been obliged to rename 

 one of the forms figured by Koch in his ' Die Myriapoden,' inasmuch 

 as it does not agree with Brandt's description as cited by Gervais. 



The number of species now described in the two genera will 

 amount to fifty-one. 



Order APTERA. 



Suborder Myriopoda. 



Division Chilognatha. 



Family Glomerid^e, Gervais. 



Genus Sphcerotherium, Brandt. 



Div. 1. Last dorsal segment having a more or less distitict external 



rim. 



Sect. a. Anterior portion of the last segment abruptly thickened. 



1. Sph.erotherium rotundatum. 



Sphcerotherium rotundatum, Brandt, Bull. Nat. Mose. pi. 6, p. 11)8. 

 n. 1 (1833) ; Koch, Myriapoden, i. pi. 19. f. 38 (1803). 



