THORICTIDJE. — LATHRIDIIDiE. 



113 



antennae o£ individual ants, which carry them about with them 

 without apparently feeling much inconvenience. An illustration 

 of this (after Wasmann) is given by Ganglbauer (Col. Mitt. Eur. 

 iii, p. 763, fig. 40), in which Thorictus foreli is represented 

 clinging tightly to the antenna of Myrmecocystus megalocola, with 

 its antenna) and legs tucked tightly under its body. As in the 

 Paussid.e and other ants'-nest beetles, the Thorictid,e are 

 furnished with secretory tufts of golden hair, and it is very 

 probable that, as Wasmann thinks, the position of the beetle on 

 the antennae enables the ant to reach these patches, which are in 

 some cases situated on the under surface of the body, and in 

 others at the posterior angles of the prosternum. The greater 

 number appear to be associated with Myrmecocystus, but some 

 occur with Aphamogaster, Pheidole, and Tetramorium. 



[Family 41. DERODONTIDiE.] 



Small, coarsely punctured insects; antennce inserted before the 

 eyes, eleven-jointed, almost filiform, joints nine to eleven somewhat 

 thicker than the rest ; eyes prominent ; anterior coccce transverse, 

 prominent and contiyuous, the cavities closed behind, confluent; 

 posterior coxae transverse and slightly separated ; elytra entirely 

 covering abdomen; leys rather slender; tarsi five-jointed, simple; 

 abdomen with jive free and almost equal ventral segments. 



This is a very small family of doubtful position ; it contains 

 about half a dozen species belonging to two genera, Derodontus 

 and Peltastka, the former being obloug with a round thorax, 

 which is strongly toothed at the sides, and the latter oval, 

 resembling a very small Peltis. They occur in Europe, Japan, and 

 North America, and nothing is known as to the larvae or pupae 

 or their life-history. Sharp considers them to be scarcely 

 distinct from the Cleiiid.e ; Leconte and Horn place them 

 between the Latheidiid.i; and Byerhid.e, but consider that in the 

 form of the coxae they approximate to the families following the 

 Elaterldje; while Ganglbauer assigns them a position between 

 the Thorictldje and Lathridiid.e. 



Family 42. LATHRIDIIDiE. 



Minute insects, pubescent or glabrous, with the pronotum, as a 

 rale, considerably narrower at the base than elytra, rarely ovate; 

 elytra often strongly punctured, costate or nodulose ; antennce inserted 

 in front of the eyes under the anterior angles or at the side margins 



I 



