432 



PROF. B. T. LOWNE ON THE STRIJCTURE AND 



The great interest of this pouch is that the gum- glands {gl) or 

 coUeterial glands, as they are sometimes called, open by two 

 slender ducts (d) into it, and not, as is usually believed, into the 

 uterus itself. 



Although I have frequently satisfied myself of this, both by 

 section and by careful dissection, this point is of such importance, 

 that I shall enter into an examination of the vievi^s of previous 

 writers with regard to the termination of these ducts. 



It is quite possible that several distinct glands liave been con- 

 founded under the term gum -glands ; indeed it is generally used 

 for any accessory gland connected with the sexual canal. These 

 glands are generally described as opening into the vagina or 

 uterus. Stein (24) gives a great number of figures representing 

 the oviducts, uterus, and appendages in the Coleoptera ; in many 

 it is difficult to identify the gum-glands. In SydropMlus (I. c. 

 Taf. iv. fig. iii) he represents the gum- glands as opening into the 

 upper part of the ovarian duct. They are branching tubules 

 which evidently form part of the ovary itself ; and, judging by 

 his excellent figure, are identical with the so-called gum-glands in 

 the Blowfly. 



Except in the Hydrophylidse, Stein considers the gum-glands 

 as a portion of what he terms the " apparatus of fertilization " 

 {Befruc'hUmgs-Organe)^ and represents them as if they opened into 

 the spermatophorous capsules or their duct ; although in many 

 cases it is almost evident from his figures that they open into the 

 oviduct. In some of his figures the spermatophorous capsules 

 are represented opening into the oviduct (Taf. i. fig. vi), whilst 

 in others they are correctly represented opening into the uterus, 

 whilst the gum-glands open into the oviduct (Taf. ii. figs, i, ii, 

 and iii). 



Tracing the gum-gland in the Blowfly' from its ovarian ex- 

 tremity, it lies first under and close to the ovarian duct ; it then 

 leaves this duct and comes into relation with the spermatophorous 

 capsule, around which it forms a loop. The duct of the gum- 

 gland commences at the termination of this loop, and is easily 

 overlooked, as it is in close contact with the duct of the spermato- 

 phorous capsule, round which it turns and runs forward in 

 close contact with the dorsal wall of the uterus and oviduct to 

 terminate in the bulb of the oviduct. It is not difficult to under- 



