200 Mr. A. G. Butler on the genus Thelyphonus. 



17. Virgulina Hcmpricliii [EJir.). 



18. tessera [Ehr.). 



19. americana {Ehr,). 



20. Bifarina saxipara {Eh-.). 



21. Textilaria agglutinans, D''Orh. 



22. gibbosa, D' Orb. 



23. striata, Ehr. 



24. globulosa, Ehr. 



25. Spiroplecta americana, Ehr. 



26. rosula, Ehr. 



27. Bigenerina digitata, Z)' Orb. 



28. Heterostomella tumens (Ehr.). 



29. Verneuilina pygma^a [Egger). 



30. Globigerina cretacea, D' Orb. 



31. Planorbulina ammonoides [Rss.). 



32. Planulina ariminensis (D^Orb.). 



[To be continued.] 



XXVIII. — A Monograph of the Genus Thelyplionus. 

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



[Plate Xin.] 

 The first monograph of this genus was that by M. Lucas in 

 the ' Magasin de Zoologie ' for 1835, in which six species 

 were recognized, five of them being then described for the 

 first time. 



In 1843 Koch added five new forms in his ' Arachniden,' 

 since which time three others have been diagnosed, one of 

 them being probably the adult type of a previously described 

 species. 



I have now to add eight more species, which, considering 

 that one of those described by M. Lucas is appai-ently a young- 

 form of the T. proscorpio of Latreille (hitherto confounded 

 with T. caudatuSj Linn.), will bring the number of known 

 Thelyphoni up to twenty-one. 



In the present paper I have separated the species into three 

 sections according to the number of teeth on the second joint 

 of the cheliceres. This important character, which appears to 

 be very constant, has been much neglected in descriptions, 

 and still more so in figures of the various species ; very little 

 attention has also been paid to the amount of rugosity, or the 

 hairiness of the cheliceres, legs, &c., though in the order Coleo- 

 ptera such characters are considered of the utmost importance, 

 as, indeed, they may be shown to be in the present order. 



The species of Thelyphomis in tlieir general appearance 

 remind one strongly of the two genera Liicanus and Ncpa. 



