NORTH AMERICAN COLEOPTERA. 105 



country from the Pacific Coast were undoubtedly brought in articles of 

 commerce. It has also been described from Madagascar, St. Helena and 

 Madeira, and under three different generic names. 



Note. — Lest some ambiguity may be apparent in the use of the term " mar- 

 gined" as used witii reference to the prothorax in the preceding pages, it may be 

 stated that in all my writings it will be understood to mean that the prothorax is 

 limited laterally by a narrow surface, which is usually raised, but which in some 

 cases may be continuous in elevation with the general surface and limited inter- 

 nally by a striated or grooved line. 



Again when the term "edge" is employed in describing the pronotum, it will 

 have reference to the boundaries of that part when considering the vertical cross- 

 section, and the phrase would then read " edges acute," or " edges rounded." 

 When the term " side" is spoken of, it will relate to the conformation of the lateral 

 boundary of the pronotum with reference to its nature as a line, this line being the 

 horizontal projection of the boundary as seen when viewed perpendicularly, and 

 the phraseology to be employed will be " sides arcuate, straight or sinuate," or 

 various modifications of these terms. 



These matters are brought up at this time in order, if possible, to render the 

 phraseology a little more concise and uniform. A striking example of this want 

 of uniformity, is seen in the use of the term "margined," Dr. Sharp using the 

 word as defined above, while one or two of our leading coleopterists have used it 

 to indicate that the edges of the pronotum are acute, which is evidently an abnor- 

 mal use, and one, the meaning of which, would be decidedly unintelligible to a 

 person not familiar with this particular employment, however well-versed he 

 might be with its usual signification as an English word. 



In the case of Narthecius, as defined in the table of genera composing Group I 

 of the Cucujinae, the expression " prothorax margineil," has reference to the sur- 

 face included between the lateral striae and the sides of the pronotum, and per- 

 haps it would be less ambiguous to saj' in this ease that the prothorax is striated 

 in Nartheriu.i and not striated in Pediacas, because of the comparativeh' great 

 distance between these striae and the sides in the former genus. 



Bibliography and Synonymy. 



SILVANUS. 



Latr. Gen. Crust, et Ins. Ill, p. 20, 1.S07. 

 Leptus Puftseh. Faun. Aus. Ill, s. 150. 

 1. S. surinamensis (Linn), Syst. Nat. I, II, 565. 29. 

 Dermestes surinamensis Linn, Syst. Nat. 1. c. 

 Tenebrio suri7iamensis Degeer. Ins. V, 54. 5. 

 Dermestes sexdenlaius Fab. Syst. El. I, ,il7, 25. — Panz. Faun, (ierni. 14. 11. 



Blisson Ann. Fr., 1849, p. \6?,. 

 Ips/rumentaria, OUv. Ent. II, 18, 10, 14. 

 Colydium frumentarium Fab. Syst. El. II, 557, 11.— Herbst. Kiif. VII. 283, 4. 



TRANS. AMER. ENT. SOC. XI. (27) FEBKUARV, 1884. 



