304 Mr. W. Wesclie's Noks on tlic value of 



weighed, and they will always in the ipalc afford specitic 

 characters. 



Literature. 



1. Recherches anatomiques. L. Dufour, 1851. Mem. 

 Pres. Ac. Sci, Paris, tome xi. 



2. Genus Phronia, A. Dzicdzicki, 1889. Hor. Soc. 

 Entom. Ross, tome xxiii. 



3. The Blow-fly. B. Thomson Lowne. London, 1895. 



4. Morphologic de rarmuro genital des inscctcs. A. 

 Peytorera. Paris, 1895. 



5. Mnscadomcstica,Ju. A. Berlesi. Riv. Patol. Vegetal. 

 ix, 1902. 



6. Genitalia of iScatophar/a. W. Wesche. Jour. Quekett 

 Micr. Club. Ap. 1903. 



7. Hypopygium of the Dolicliopodida?. Rob. E. Snod- 

 grass. 1904. Proc. Cal. Acad. Science. Ser. 3, vol. iii, 

 Zool. No. 11. 



8. Genus Sarco^jhaga. F. du Rosille. Mem. Soc. 

 Linneenne du Nord de la France. Amiens, 1905. 



9. Genitalia of Glossina |)rt/pa/is, Des. W. Wesclie. 

 Jour. Quekett Micr. Club. 1905. 



10. Genitalia of both the sexes in Diptera. W. Wesche. 

 Trans. Linn. Soc. Lend. Ser. 11, Zool., vol. ix, 1906. 



11. Male genitalia of Pcriplanda orientaJis, L. W. 

 Wesche.. Jour. Quekett Micr. Club. Ap. 1908. 



Suiyph mental' II Note. Since writing the above paper I 

 have, with the aid of Dr. J. H. Wood, who has kindly 

 supplied the material and notes on the external characters, 

 made preparations and dissections of some Phorida3 which 

 are included in Brues' genus of Apiocha^ta. The male 

 genitalia throughout show a striking generic character in 

 the presence of pads of chitinous cilia, supported by asym- 

 metrical rods and rings, forming an organ of extremely 

 complicated structure, whose minute size makes it difficult 

 to study or understand, but I can in several species see 

 the ejaculatory duct opening into the bases of the struc- 

 tures supporting the chitinous cilia. This arrangement is 

 quite distinct from the apparatus found in such FJiora as 

 incrasmta, Mg., or mrrinervis, Beck., and a]:)pears to 

 characterise the group and is good evidence in favour of 

 the natural character of Brues' genus. It is interesting 



