Horn.] xZO [Feb. 21, 



Philhydrus. Solier. 

 Our species may be divided into two sections : 



Mesosternum with longitudinal crest Philhydrus. 



Mesosternum simple, rarely with transverse cariua. Helochures. 



The section Philhydrus is again divisible in the following manner : 



Presternum elevated in form of crest Group I. 



Presternum simple Group II. 



The first group contains comparatively few species. 

 Presternum feebly cristate. 



Elytra with rows of large punctures normatus. 



Elytra densely punctulate carinatus. 



Presternum strongly cristate, crest more elevated 

 in front. 

 Elytra distinctly punctulate. 



Mesosternal crest at free angle mucronate. \ * 



' nebuloms. 



Elytra nearly smooth. 



cristatus. 



pectontUx. 



Mesosternal crest acute but not mucronate. -j 



P, normatus, Lee. Proc. Acad. 1861, p. 341. 



Oblong oval, narrower in front, moderately convex, shining. Head 

 moderately but not densely punctured. Thorax gradually narrowed to 

 the front, sides moderately arcuate, surface more finely punctured than 

 the head, punctures at sides more distinct but not denser. Elytra broadly 

 oval, broadest behind the middle, surface shining and with ten entire 

 striae of coarse punctures, of which the outer two are closer and slightly 

 sinuous, and a short scutellar stria of smaller punctures, marginal space 

 smooth ; interatrial spaces very minutely and sparsely punctulate. Body 

 beneath black, shining, sparsely punctulate and pubescent. Femora 

 piceous, pubescent except at tip, tibiae and tarsi piceous-rufous. Palpi 

 and antennae testaceous, the club of the antennae darker. Mesosternum 

 with a crest not very prominent, presternum moderately cristate, crest 

 not more prominent in front. Length .20-.22 inch ; 5-5.5 mm. 



Var. Piceous, disc of thorax somewhat darker. (Type, discolored.) 



Var. Ochraceous, with labrum, frontal suture, occiput and large discal 

 space of thorax black. Elytral punctures surrounded by a transverse 

 quadrate piceous space. 



The latter variety is the normal coloration of the species, the type 

 being a discolored specimen. 



Occurs from San Francisco southward to Cape San Lucas, and thence 

 eastwai'd to Arizona. 



P. carinatus, Lee. Proc. Acad. 1855, p. 370. 



Oblong oval, slightly narrower in front, convex, black, very shining, 

 thoracic margin piceous, surface equally punctured with moderate punc- 



