92 Mr. R. Templeton's Descriptioiis of 



For want of specimens I have been unable to make such a minute 

 examination of these insects as would enable me to speak upon the 

 propriety of Latreille's entirely sinking the Petrobius of Leach ; but 

 I may be allowed to observe, that the littoral habits of that group 

 seem to give it as great a claim to be considered distinct from the 

 others, as that which separates the Nebriee and Helobice, or Bledius 

 and Hesperophilus amongst the Coleoptem. 



Descriptions of the Irish Species of Thysanura, 

 bi/ R. Tbmpleton, Esq. 



INSECTA. — Ametabolia, Leach. 



Thysanura, Leach. 



Lepismad^. Leach. 

 Lepisma, Linn. 



Sp. 1. Saccharina, Linn. 



Common, John Templeton. 



FoRBiciNA, Geoff. 



Sp. 1. PoLYPODA, Linn. 



Plate XI. Fig. 1. 

 Very common in dry stone ditches and mossy places. 



Fig 1. Outline of the animal magnified. la. Head seen in front. \h. Su- 

 periorly. 1 c. Antenna. 1 <^. Last joint of the palpus. 1 e. The 

 foreleg. 1/. The hind foot. \g. Jaws, which are very thin and 

 membranous. 1 h. Inside, showing the auxiliary legs; the back is 

 placed to the right. 1 L The auxiliary foot, with which it ascertains 

 the presence of the object against which the tail is adpressed. \k. h. 

 scale, much magnified, to show the lines producing the iridescence, from 

 9,000 to 11,000 in an inch. 



Petrobius, Leach. 



Sp. 1. Maritimus, Leach. 

 Common everywhere on our rocky shores. 



PoDURAD^, Leach. 



Orchesella, n.g. 



Antennae 6- or 7 -jointed, nearly as long as the body, filiform; fork 

 developed. 



the Linnaean cabinet, 1 have not been able to find a single species of the order. 

 Mr. Templeton's species, which he names polypoda, enters into the second section, 

 and is evidently identical with Dr. Leach's polypoda. 



