276 GEO. H. HORN. 



•sides paler. The mesosternum is slightly protuberant and within 

 the recognized limits of variation in mfuscatns, although Dr. Le- 

 Conte states that the mesosternum is simple. 



This species has been compared, very properly, with glohosus Payk., 

 both species belonging to Anaesena Thorns. 



Occurs from Oregon southward to San Diego, eastward to Wyoming 

 and Michigan, thence south to New Mexico. 

 o 



In closing a paper it is always a pleasure to acknowledge the as- 

 sistance given by friends to whom, during the progress of my own 

 studies, my views have been made known and subjected in advance 

 to that criticism which must follow publication. Therefore, to Dr. 

 Hamilton, Messrs. Blanchard, Ulke and Schwarz, I express my 

 thanks for critical aid as well as for the loan and gift of material. 



^ Bibliography and Synonymy. 



LeCoiite, Synopsis of Hydrophilidse, Proc. Acad. 1855, pp. 356—375. 

 Horn. Revision of the gen. and spec, of Hydrob., Proc. Amer. Philos. Soc. 1873, 

 pp. 118—137. 



PIIIL,YDRIIS Sol. 



P. carinatus Lee, Synopsis p. 370; Horn, Revis. p. 126. 

 P. fucatus Horn, Revis. p. 127. 



P. cuspidatus Lee. (Hydrohius), Proc. Amer. Philos. Soc. 1878, p. 597. 

 P. nebulosus Say (Hydrophilm), Long's E.^ped. ii, p. 277; edit. Lee. i, p. 183; 

 Horn, Revis. p. 127. 

 macuUfrons Motsch., Bull. Mosc. 1859, iii, p. 179. 

 var. cristatus Lee, Synopsis, p. 370 ; Horn, Revis. p. 127. 

 latiusculus Motsch., loc. cit. p. 178. 

 pectoralis Lee, Synopsis, p. 370; Horn, Revis. p. 127. 

 nbttisinsculus Motsch., loc. cit. p. 179. 

 P. ocliraceus Mels., Proc. Acad, ii, p. 101 ; Lee, Synopsis, p. 371 ; Horn, Revis. 

 p. 129. 

 simplex Lee, New Species. 1862, p. 24. 

 P. perplexus Lee, Synopsis, p. 371 ; Horn, Revis. p. 130. 



fuscns Motsch., loc. cit. p. 178. 

 P. cinctus Say (Hydrophilus), Long's Exped. ii, p. 276; edit. Lee. i, p. 182; 

 Horn, Revis. p. 129. 

 limhalis Mels., Proc. Acad, ii, p. 101. 

 P. censors Lee, New Species, 1862. p. 24 ; Horn, Revis. p. 129. 

 P. californicus n. sp. 



latiusculus X Horn, Revis. p. 130. 

 P. Hamiltoni n. sp. 



P. diffusus Lee, Synopsis, p. 371 ; Horn, Revis. p. 129. 



P. reflexipennis Zimiu., Trans. Am. Ent. Soc. 1869, p. 250; Horn, Revis. ji. 129. 

 (imjHstulus Casey, Contributions ii, p. 83. 



