316 LAMELLICOENIA. 



characters that the anterior tarsi are simple in both sexes, and the tibiae tridentate, i. e. 

 without trace of a fourth upper tooth. The size ranges from 17 to 21 millim. 



In the Munich catalogue Scarabceus antillarum of Beauvois is given as a probable 

 synonym of L. tumulosus. The figure cited, however, plainly refers to a species with 

 narrow bidentate clypeus, like L. nasutus. 



3. Ligyrus gibbosus. 



Scarabceus gibbosus, De Geer, Mem. Ins. iv. p. 322, t. 19. f. 7 '. 



Ligyrus gibbosus, Leconte, Proc. Ac. Phil. 1856, p. 20 2 ; Horn, Trans. Am. Ent. Soc. 1875, p. 143. 



Podalgus variolosus, Burm. Handb. der Ent. v. p. 121 3 . 



Geotrupes juvencus , Fabr. Ent. Syst. i. p. 32. 



Podalgus juvencus, Burm. Handb. der Ent. v. p. 121*. 



Ligyrus juvencus, Burm. loc. cit. p. 542. 



Ligyrus morio, Leconte, Proc. Ac. Phil. 1856, p. 20 5 (apud Horn, Trans. Am. Ent. Soc. 1875, p. 143) . 



Bothynus obsoletus, Leconte, Journ. Ac. Nat. Sci. 2nd ser. i. p. 87 c . 



Bothynus neglectus, Leconte, loc. cit. 



Hab. Noeth America 12345 6 # — Mexico, Mazatlan (Dr. Ccesar, sec. Sturm in coll. 

 Salle), Durango city (Hoge). 



The single example from Sturm's collection agrees precisely with North-American 

 specimens of L. gibbosus (juvencus) with which I have compared it. Numerous so-called 

 species have been founded on slight variations which are not more marked here than in 

 other species of the genus, and I follow Dr. Horn in re-uniting them. L. gibbosus is 

 closely allied to L. tumulosus ; but is generally shorter and relatively broader, with 

 the teeth of the clypeus approximated, the frontal carina median and entire, and the 

 tubercle and pit of the thorax more strongly developed. The single specimen from 

 Durango city is much worn, but is evidently referable to the same species. 



4. Ligyrus ruginasus. 



Ligyrus ruginasus, Leconte, Proc. Ac. Phil. 1856, p. 20 \ 



Sab. Noeth America, Texas l . — Mexico, San Pedro in Coahuila (Dr. Palmer), Chi- 

 huahua city, Villa Lerdo in Durango, Iguala in Guerrero (Hoge), Ventanas (Forrer). 



Distinguished from all other species of the genus by its pointed and submucronated 

 clypeus and reddish-testaceous colour ; the anterior tarsi are simple in both sexes, and 

 the tibia? tridentated. 



5. Ligyrus laevicollis. (Tab. xvm. fig. 16, c? .) 



Oblongo-ovatus, niger, politus, subtus piceo-rufescens ; clypeo valde angustato apiceque dentibus duobus approxi- 

 mates, fronte tuberculis duobus mediocriter distantibus, conicis, acutis ; tborace subelongato, disco la?vi, 

 lateribus disperse punctulatis, tuberculo antico parvo obtuso foveaque parva triangulari baud profunda 

 parce punctato-rugulosa ; elytris subgrosse punctatis, striis geminatis utrinque tribus, iuterstitio lato sub- 

 suturali plerumque lsevi ; pygidio fere laavi, basi tantum confiuenter punctulato, cJ valde convexo, $ 

 planato-deelivi. Tibias anticse dente 4° brevissimo ; tarsi antici S 2 simplices. Mandibular bidentatas. 



Long. 18-22 millim. <$ § . 



