306 Royal Society :• — 



" On the Digestive and Nervous Systems of Coccus hesperidum.'' 

 By John Lubbock, Esq., F.R.S., F.L.S., F.G.S. 



In the early part of last spring I began to investigate the anatomy 

 of this interesting little insect, with the intention of studying only 

 the organs connected with the development of the ova and pseudova. 

 It soon, however, became evident that the structure of the intestinal 

 canal, on the one hand, had been entirely misunderstood by those 

 who had previously examined it ; and on the other, that the nervous 

 system, far from being similar in all specimens, varied in the most 

 extraordinary manner. It is therefore proposed in the present com- 

 munication to give a very brief description of the digestive organs 

 and of the nervous system. 



Intestinal Canal. 

 (Magnified 30 diameters.) 



Ramdohr and Leydig are the only two naturaUsts, so far as I 

 know, who have published any original remarks on this subject. 



Ramdohr says, " Die Speiserohre kurz und enge. Der Magen 

 vorn ein wenig erweitert, lang und vollig durchsichtig, so dass man 



die dunkeln Contenta darin sieht Der Dunndarm ist leer, etwas 



weiter als der Magen, durchsichtig, bisweilen faltig. ... Die Gallge- 

 fasse fehlen, wenigstens konnte ich nicht die geringste Spur davon 

 entdecken." This description, however, has reference to Chermes 

 Alni. 



According to Leydig (Zeitschr. f. Wiss. Zool. v. tab. 1. fig. 1), 

 the canal in Coccus hesperidum consists of a short oesophagus, a large 



