142 C. ZIMMERMANN, M. D. 



" I. — BosTRYCHi : tarsi filiform, evidently 5-jointed ; beak obso- 

 lete; containing Plati/pm, Cn/pturjus, JL//Ioferm, BosfricJuis:. 



II. — EcooPToaASTERES : 3rd joint of tarsi bilobed ; beak very 

 short and thick ; ventral segments of abdomen excavated ; containing 

 Eccoptogaater. 



III. — Hylurgi : 3rd joint of tar^i bilobed ; beak very short and 

 thick ; abdomen cylindrical ; containing Phloeotribus, Hylesinus, Dcn- 

 droctonus, Hylurgus." — Lec] 



Tribe I. — Bostrychi. 

 The beak is scarcely developed, but the great resemblance of these 

 beetles in the i-iietliod of life, and the structure of the body, (both in 

 the larva and the perfect insect), with the genuine Hijlurgi, demon- 

 strates their true position in the system. They are distinguished from 

 allied groups by the filiform tarsi, the 3rd joint of which is not dilated 

 or bilobed. 

 Club of antennas without traceof articulation; eyes round. 



1, Prothorax truncate in front; elytra depressed; 1st joint of tarsi as long 

 as the others united.* Platypus Herbst, V. 128. 



Club of antennse articulated, eyes transverse, emarginate. 



2. Prothorax with a hood-like extension over the head; elytra not depres- 

 sed ; 1st joint of tarsi short; the subgenera are: 



a. The separation between the three joints of the antennal club trans- 

 verse and visible both on the inner and outer surface of the club. 



Crypturgus Er. 



6. The separation between the joints of the antennal club concentric, 

 and visible only on the anterior surface, being covered on the other 

 side by the first joint Xyleborus Er. 



c. The three joints of antennal club separated from each other as in 

 Cryturgus, but only visible on the anterior surface, being concealed on 

 the other as in Xyleborus Bostrychus Fabr. Syst. 59. 



CRYPTURGUS Er. 



All the species belonging to this genus have the tibiae compressed 

 but slender, and scarcely dilated towards the tip ; according to differ- 

 ences in the form of the prothorax, the front femora, and other parts 

 of the body they may be arranged in three divisions. 



A.- — Prothorax longer than wide; antennal club fringed at the sides 

 with long hairs; front femora toothed at tip; outer surface of the an- 

 terior tibiae, as in Platypus, with teeth like transverse ridges. •!• 



« No new species are described in the part of the memoir relating to Platy- 

 pus, M'hich is therefore omitted. — Leg.] 



t This division corresponds with the genus Corthylas Er.", which differs from 

 Crypturgus by the funiculus of the antennae consisting of but o«e joint, instead 

 of two. The plan of arrangement pursued by the author does not take cogni- 

 zance of the number of joints of the funiculus, and therefore definitions of the 

 the two genera naturally fall together. — Leg.] 



