264 



TRANSACTIONS OF THE 



will readily include not only the present species of triar- 

 thritic reference, but also of the Paradoxides Boltoni, 

 and P. scaraboides^ which do not possess all the generic 

 characters of Paradoxides as now extant. The above 

 named species differ generically, in the form and propor- 

 tions of the abdomen and tail, from each other and from 

 those parts in the present species. 



Generic characters in order to be practically useful, 

 should always be brief; in accordance with this rule, the 

 following modification of the characters of Paradoxides 

 is offered. 



Genus Paradoxides, 



Buckler^ destitute of oculiforra tubercles, anterior bor- 

 der semicircular, middle lobe marked with transverse 

 furrows or bands. 



Abdomen, composed of transverse bands or articula- 

 tions continuous with those of the lateral lobes. 



Under such modification we are prepared to introduce 

 the new species before us. 



1. Paradoxides TRiARTHRUs. (H.) PI. 15, fig. 5. 



Buckler hemispherical, middle lobe nearly twice the 

 width of the lateral lobes, and marked with three trans^- 

 verse lines, the two superior interrupted in the middle, 

 lateral lobes plain, narrower above, subventricose. Ab- 

 domen, with at least four articulations, those of the mid- 

 dle being continuous with those of the lateral lobes^ 

 which diminish in descending order; tail continuous 

 with the abdomen, inferior margin rounded. 



The whole animal is rather broader than long; length 

 of the body nearly equal that of the buckler; three or 

 four small spines arranged transversely on the middle of 



