210 Dr. David Sharp's Studies in Rhynchophora. 



conclude that 200.000 is a minimum number for the 

 existing species, of which about 25,000 are described. 



Hence it is not a matter of surprise that I have not yet 

 been able to obtain a sufficient knowledge to enable me to 

 speak positively as to the objects of my work. I am, in fact, 

 unable to demonstrate the value of the male structures 

 for taxonomic purpose, yet I have done enough to convince 

 myself that they are probably of great value. ' But I fear 

 the task I have undertaken is likely to prove too much 

 for me to accomplish, and I therefore publish this pre- 

 liminary note in the hope that it may help to remove 

 certain misconceptions that are prevalent, and may be of 

 use to other students. 



The morphology of the male genital tube is really very 

 simple. It may be reduced to an elongate continuous 

 tube, which is made to appear shorter and more com- 

 plicated by a system of imaginations, in some respects 

 comparable to an old-fashioned telescope. 



Certain of the parts have received names from previous 

 writers, and, as I shall have to refer to these. 1 will here 

 mention the more important, viz. : — 



1. Lindeman, Vergleichend-anatomische Untersuchung 



iiber das maenliche Begattun'gsglied der Bor- 

 kenkaefer. Bull. Soc. Imp. Moscow, vol. 49, 1875, 

 pp. 196-252, 5 pis. 



2. Verhoeff, in Abdominal segmente und Copulations- 



organe, etc. Deutsche ent. Z?itschr. 1893, p. L56. 

 pi. iv. figs. L26- 1 10. 



3. Verhoeff, Ueber das Abdomen der Scolytiden. Arch. 



f. Naturgesch. 62, 1896, 1, pp. 110 111. 2 pis. 



4. Hopkins, on the genus Pissodes. U.S. Dep. Agric. 



Ent. Techn. Ser. 20, part 1. 1911. 



5. Xihslin. as already referred to on the foregoing; 



page. 



Nos. 1, 3 and 5 refer to Scolytidae, a very exceptional 

 and difficult group of Rhynchophora; while No. 2 is but 

 brief, and comparative with other Coleoptera, and, again, 

 No. 1 relates only to one genus. Hence the information 

 as to the genitalia of the greal division is very small. 



In figs. 1 and 2 I uive a scheme of the arrangement of 

 the tube in Rhynchophora. These two figures are purely 

 diagrammatic, and in some ways do not convey an accurate 



