Anatomy of the Male Genital Title in Coleoptcra. 569 



{d) with the sides curved up, and another plate (e) below it, and 

 this is produced into a blunt median keel (/) ; there is a large 

 diverticulum ((/) as in Aromia. A considerable part of the sac is 

 beset with small, chitinous teeth. 



Among the forms of this large family that we have 

 examined there is a great uniformity of type, the median 

 lobe having the orifice at the tip and extending along the 

 side, the sclerites on the dorsal and ventral aspects being 

 separated by a membrane running along each side, from 

 orifice to foramen ; the base of median lobe prolonged 

 into two struts ; tegmen ring-shaped, with a divided pro- 

 jecting process, the division generally very deep ; internal 

 sac long, projecting into the body forwards beyond the 

 median foramen in the state of repose. 



It is in the great development of the sac, and the diver- 

 sities in its armature that we must seek the peculiarities 

 of the family. Farandra, so far as the genital tube is 

 concerned, appears to be the lowest form ; in it we have 

 found no specialisation of importance. A general resem- 

 blance between the tube of Parandra and that of Cucu- 

 joidea is evident at first sight (compare Farandra, fig. 

 219 with Cucujus, fig. 97, or Fassandra, fig. 96). In the 

 section phylogeny we have shown reasons for supposing 

 that this general resemblance may be deceptive. 



We have examined various other Cerambycidae without 

 finding anything to make it necessary to increase the 

 length of this memoir by including them. But there is 

 one point we must mention briefly. Bordas has pointed 

 out that in certain Cerambycidae there appear to be present 

 two ejaculatory ducts. In other words that the stenazygos 

 is wanting. We also have observed this fact in Gnoma 

 (PI. LXXV fig. 220) and in some species of Monohavimus 

 (PI. LXXVI figs. 221 and 221r0. 



That this fact is of much morphological importance is 

 not clear to us. It may perhaps be due to the great 

 extension of the sac (or eurazygos). And in fact in another 

 closely allied species of Ifonohammtcs we have found a 

 distinct stenazygos. The structure as it has appeared to 

 us in Monohammus longicornis is shown in PI. LXXV fig. 

 221, and in 221a where the sac is everted. It is then 

 seen to be studded with small spines, and bears two 

 diverticula, thus acquiring a singular resemblance to the 

 head of a dog ; and it will be seen that there is a short 



