Mr. Newport on the Class Myriapoda, Order Chilopoda. 377 



successive series of epithelial cells that line the interior of those organs, the 

 fluid contained within, and into which these cells and their nucleoli are re- 

 solved, being the proper secretion. When this is expended too frequently, and 

 the organ in consequence is excited by what we may regard as the stimulns of 

 want, the secreting epithelial cells are hastened in their development, and the 

 fluid into which they are resolved is imperfectly elaborated, and its properties, 

 doubtless, are less active. The gland by which the poison of the centipede is 

 secreted has not hitherto been described. Leeuwenhoek discovered at the 

 apex of the mandibles an orifice that communicated internally with an elon- 

 gated cavity, and he also saw a drop of fluid exude from the orifice, but he 

 does not appear to have discovered the true secreting gland. Although I do 

 not now intend to enter on an examination of the internal organs of Myria- 

 poda, I may here briefly state that I have been somewhat more fortunate in 

 this respect, and not only have confirmed Leeuwenhoek's observation in re- 

 gard to the existence of a longitudinal opening at the inner margin of the 

 apex of the mandible, but also have traced backwards a sac with which it 

 communicates, and have discovered the gland of which this sac is the reservoir 

 or efferential cavity. The gland itself extends backwards from its junction 

 with the sac at the articulation of the claw and atrophied tarsal and tibial 

 joints to their articulation with the femoral portion of the mandible, of which 

 it occupies the whole length, situated almost close to the external surface be- 

 neath the tegument, abundantly supplied with vessels and nerves. 



Familia 4. ScoLOPENoRiDiE. 



Segmenta podophora 21 vel 23. Pedes posteriores incrassati; articulo primo vel secundo 

 spinoso. AntenncesvXixAaXss, l7-20-articulatae. 



Subfamilia 1. ScoLOPENDRiNiE. 



Genus 5. Scolopendra. 



Segmentum cephalicum cordatum, imbricatum. Oculi stemmatosi, utrinque 4. Antenna 

 attenuatae, 18-20-articulatae. Spiracula valvularia, in paribus 9. Pedum paria 21. 



Divisio 1. Parvidentatce. 

 Denies labiales numerosi minimi, uniformes, coadunati. 



3 D 2 



