1854.] 117 



New York. Less densely and more finely punctured than those above described, 

 the punctures being more distant from each other than their own diameters, ex- 

 cept on the head, which is confluently punctured ; the punctures of the thorax 

 are smaller than those of the elytra, and the lobe of the base is only slightly 

 prolonged. The body is somewhat acuminate at each end. 



4. L. ater, ovalis, utrinque attenuatus, convexus, niger nitidus, cinereo- 

 pubescens, thorace subcanaliculalo subtiliter punctato, basi longius lobato, ely- 

 tris sat dense punctatis, punctis ad suturam et apicem subtilioribus, antennis 

 pedibusque nigris, prosterno sulcato. Long. -08. 



Mississippi, Dr. Schaum. Distinguished from L. obscurus by its blacker color, 

 and by the body being more sharply acuminate at each end ; the thorax is longer, 

 and the basal lobe is more obvious. 



5. L. nitidulus, ovalis utrinque attenuatus, convexus niger nitidus, parce 

 cinereo pubescens, thorace subcanaliculato, subtiliter punctulato, basi modice 

 lobato, elytris minus dense punctatis, punctis ad suturam apicem et marginem 

 subtilioribus, antennis pedibusque nigris prosterno profunde sulcato. Long.*07. 



Georgia, in Habersham County. Of the same form as L. ater, but more shin- 

 ing, with the punctures of the elytra larger, less dense, and becoming smaller 

 towards the edges. 



3 V 



6. L. o v a t u s , breviusculus ovatus, utrinque attenuatus, convexus, niger 

 nitidus, densius cinereo-pubescens, thorace basi vix lobato, vix punctulato, elytris 

 minus distincte punctulatis, antennis pedibusque piceo-rufis, prosterno profunde 

 sulcato. Long. 06. 



Georgia; found also in Louisiana, according to Mr. Motschulsky. Smaller 

 and much broader than any of the preceding species. The punctures of the 

 elytra are not obvious, and those of the thorax, although dense, are so fine as to 

 be hardly visible. 



Physemus j Motsch. 



Oculi, labrum, et mandibulae libera; antennae tenues clavatae, clava in fovea 

 superna ad angulo thoracis antico recepta; tarsi liberi. 



Mr. Motschulsky informs me that the insect here described is congeneric 

 with the Russian Physemus velutinus mentioned by him in his catalogue of the 

 Hydrocanthares of Russia, (p. 12,) and I have acordingly adopted the name 

 proposed by him. The insect is of small size, broadly ovate in foyn, subacute 

 posteriorly. The antennae are longer than the head, the first four joints are 

 thick, the second being a little shorter, the fifth and sixth are somewhat less 

 thick, the seventh slender, as long as the sixth: the club is oval, not much 

 broader than the first joint, and apparently solid, though with a high magni- 

 fying power, it appears indistinctly articulated. The most remarkable char- 

 acter is that this club is received in a deep hole, each side of the thorax, on 

 the zipper surface, just behind the anterior angle. The feet are slender, and 

 formed as in Linnichus. 



1. P. minutus, breviter ovatus, utrinque attenuatus, convexus niger, 

 densissime subtiliter punctulatus, cinereo-pubescens, prosterno haud sulcato, 

 pedibusque rufo-piceis. Long. -03. 



Colerado river, California, Has the habits of Linnichus, and appears when 

 water is thrown on the banks. 



10 



