334 



CALIFORNIA ACADEMY OF SCIENCES. 



S. Zimmermanni Schaum.— Tho- 

 rax latitudine lougior, ante basin 

 utrinque obsolete bifoveolatus. Co- 

 leoptera in medio thorace dimidio 

 latiora, tota crebre subtiliter punc- 

 tata. Long. I lin. 



Carolina. 



E. punctatUS Casey. — (Protho- 

 rax) ; disk not foveate along the base 

 but narrowly and feebly eroded. Ely- 

 tra widest in the middle, where they 

 are nearly twice as wide as the latter 

 (pronotum), coarsely, rather strong- 

 ly and somewhat densely punctate. 

 Length, 1.4 mm. 



Michigan. 



It will be readily seen that E. pwictahis is a more robust 

 species than the one described by Schaum, and that the 

 elytral punctuation is probably much finer in the latter: the 

 length, I of a line, is also somewhat greater than 1.4 mill. 

 In E. pundutus there are no basal fovea) as in E. vestalis and 

 Choleriis Zhninermanni, but instead a feebly and irregularly 

 eroded line extending across the pronotum, parallel to and 

 very near the basal margin. These dijBferences alone are 

 sufficient proof that the two species are different and show 

 most conclusively, either that the specimen with which Dr. 

 Horn compared my type was not the true Zimmermanni of 

 Schaum, or that the comparison was very hastily made. 



The most positive proof of the mutual distinctness of 

 these species, however, is found in the antennal structure. 

 In E. punclatus the antennae are strongly geniculate, precise- 

 ly as in E. vestalis, while as S. Zimmermanni has been placed 

 in Choleras Thorn., characterized by its straight antennae, 

 it is to be presumed that these organs are at least not 

 strongly geniculate in that species. 



There are many errors similar to these in the synonymi- 

 cal list referred to, which will be corrected at a future time; 

 probably more than two- thirds of the synonyms proposed 

 are incorrect, and will appear most obviously so to those 

 taking sufficient interest to compare the original descrip- 

 tions; a few of these are noted in the present pa]3er under 



the genus Actidium. 



II. 



The word genus, in the present state of entomological 

 science, scarcely admits of " a satisfactory definition, but in 



