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TEXT-BOOK OF ENTOMOLOGY 



may be the homologues of the ephemerid rhabdopods. A pair of 

 hooks, often strong and claw-like (liarpes), are situated, one near 

 the base on the inside of each clasper ; they are especially developed 

 in the Noctuidse (Smith), and appear to be present in certain Trichop- 

 tera, but this remains to be proved. This complicated apparatus of 

 claspers and hooks is utilized by those insects which pair while on 

 the wing, and is wanting in such forms as Coleoptera and Hemip- 

 tera. Besides the forceps of Panorpa, there are two pairs of 

 slender filiform appendages which need farther examination. In 

 the Diptera, especially Tipulidse, there is a pair of 2-jointed append- 

 ages or forceps, as in Limnophila (Osten Sacken). The male genital 

 armature of Diptera appears to be on the same general plan as in 



Lepidoptera, but more complicated. 



Notice should also be taken of the paired 

 uncinate hooks which are modifications of the 

 penis-sheath of the male of cockroaches (Phyllo- 

 dromia), which Haase states appear to originate 

 on the tenth ventral plate, and which probably 

 "serve to open and dilate the vagina of the 

 female, especially as a perforated penis, which 

 is highly developed in Machilis, seems to be 

 wanting in the Blattidie." (Haase.) 



The penis. - - This is a single or double median 

 style-like structure either hollow and perforated, 

 or solid, very variable in shape, receiving the end 

 of the ejaculatory duct. It is usually enclosed 

 between two lateral plates, the homologues per- 

 haps of the inner pair of sheaths of the ovi- 

 positor. In the Coleoptera, as in Carabidse and 

 Melolonthidcie, the penis is a long chitinous tube, 

 " retractile within the abdomen on the under surface as far as the 

 anterior segments." (Newport.) In the Hymenoptera, of which 

 that of the saw-flies is a type, Newport states that it " consists of 

 a short valvular projectile organ, covered externally by two pointed 

 horny plates (?) clothed with soft hairs." Above these are two other 

 irregular double-jointed plates (Fig. 202, I) surrounded at their base 

 by a chitinous ring (A.-) ; they are edged with prehensile hooked 

 spines (i). Between these in the middle line are two elongated 

 muscular parts (ni) which enclose the penis (li), and which, like 

 those in beetles, perhaps aid in dilating the vulva of the female. 



An examination of Figs. 2<)-'-5-207 will aid in understanding the 

 various modifications in beetles, etc., of this organ. 



Fio. 202. Male organs 

 of generation of Atlialiu. 

 After Newport. 



