PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 287 



This differs from all other hairy or spiny Chitons, at all nearly related 

 to it, in the mantle ornaments not being inserted into sockets, but being 

 extensions of its substance. 



24. {HempMllia Opr. MS. J non VAnncy.) NuitalUna : zona lanugosa; 

 lamin^ie centrales uniflssatiie. This section unites in a form resembling 

 KuttaUina some of the features of MUldendorfia, from which the girdle 

 •differs in being spongy and covered with soft hairs instead of short 

 shelly bristles. The shape is that of an Isclmochiton, the sculi)ture and 

 girdle of Ckwtopleura, the insertion plates and sinus almost exactly like 

 Middendorjia. Type PciUocMton lanufjinosns Cpr. sp. Lower California. 



2G«. Fannia Gray, not Robineau Desvoidy, 1830. 



29. Lorica Acanthopleura^, zona Euoplochitoni similis ; laminte obtusaj, 

 pectinatte, sinus undatus, Icvis. Type ScJcrocMton Cpr. Torres Straits, 

 Mus. Cuming, no. 42. 



Most like Unoploehitoii, from which it differs in the articulation of the 

 tail plate and the sub-central mucro. 



30a. Lucia Gould, not of Swainson, 1833. 



30c. Acanthopleura : A^alvis partim immersis, planatis ; lamiuis centrall- 

 bus pleurifissatis; sinu lobato. Type Chiton spinosa Brugiere. 



This form bears the same relation to Acanthopleura that Fannettia 

 does to Tonicia, with the additional peculiarity of Radsioid nicks in the 

 central valves. Named for Dr. Francis, once editor of the Annals and 

 Magazine of Natural History. 



31. Lorica solidissima alata: mucro hand elevatus submedianus; lam- 

 inse valvse separatte, acuta^, leves; V. post, antice tendentes; sinus mini- 

 mus; zona coriacea, fasciculatim spinulosa. Tyi^e Chiton {jiga.s Clhemnitz. 



32. {Dawsonia Cpr. (preoc.) 1873; Middendorfia Cpr. in MS. later.) 

 Lorica et zona extus ut in Acanthopleura ; laminae acutie, extus rugosa, 

 suft'ultsBj sinus planatus hand laminatus. Type Chiton Polii Philippi 

 (non Deshayes), Dalmatia. Internally Ischnoid, externall}' Acanthopleu- 

 roid. 



32a. {Beania Carpenter, not Johnstone.) Lorica et zona inter Acan- 

 thopleuram et Ischnochitonem intermedia; mucro submedianus; 1am- 

 iuse acuti, hand suffulti; zona squamis subspinosis striatis vix imbricata. 

 Type Chiton Bissoi Cuming, non Payr. C. pseiidorissoi Cpr. MS., Malta. 

 Mus. Cuming, no. 51. 



34. Lorica tenuis; valvte undata?; mucro posticus, productus, laminae 

 acutse, leves;" V. post, antice projectse, sinus planatus, laminatus, levis; 

 zona coriacea, levis, sen lanugata. Type Arthuria Jilosa Cpr., loc. iucert. 

 Mus. Cuming, nos. 23, 38. 



This has the aspect of Chcetopleura externally in sculpture, but has 

 the tail plate like KuttalUna in its structure, and like Placiphora in its 

 external appearance. 



3Grt. Aiilacochiton pars, Shuttleworth, 1853. Lorica: mucrone postico, 

 pariim siuuato; sinu lobato; zona squamulis minimis obsita, antice pro- 

 ducta. Examj)le, Lorica Angasi H. Adams, P. Z. S., 1864, p. 193. Aus- 

 tralia. 



