110 DUBLIN NATURAL HISTORY SOCIETY. 



Professor Kinahan, M. D., read a paper — 



ON THE GENERA PHILOSCIA (lATREILLE); ITEA (kOCH) ; PHILOUGRIA (kINA- 



HAN) ; COMPRISING DESCRIPTIONS OF NEW BRITISH SPECIES. 



(with a PLATE.) 



In an " Analysis of the British Oniscoidea" read before Section D of the 

 British Association, at their recent Meeting in this city, and afterwards 

 published in your Transactions, reasons were given for re-establishing 

 the genus Philoscia {Latreille), which M. Edwards, Dana, and others, 

 are inclined to incorporate with the genus Oniscus. As first de- 

 scribed, the genus included but one species, the Oniscus muscorum 

 (ScopoU), Oniscus sylvestris {Fabn'cius). To-night I have to announce 

 another species of the genus, which confirms me in the propriety of the 

 establishment of this genus, as it agrees with Phil, muscorum in all those 

 characters which led to the generic separation of that species from 

 Oniscus. 



The genus Philoscia, though established by Latreille, appears to have 

 been unknown to all the German authors who have written on the group, 

 with the exception of Zaddach, who gives a very fair description of it. 

 H, Schaeffer states: — *' Philoscia: Up to this, but one figured species 

 is known, namely, 0. muscorum (Scopoli). Whether the species 0. syl- 

 vestris here referred to is properly cited here may be questioned ; to me 

 the genus and species is unknown." Milne Edwards contents himself 

 with copying Leach's description of the species ; wliile LerebouUet 

 evidently has never seen the typical species, as he describes a well- 

 marked species of Oniscus for it. This is singular, as the animal is one 

 of the commonest of the group in Ireland and England, and, Zaddach 

 states, also common in some parts of Germany. 



The genus Philoscia and its relations were so fully discussed in my 

 former paper, that it is unnecessary here to do more than briefly describe 

 the species and genus. 



Family.— PHILOSCID^. ^ 



Genus 1. — Philoscia {Latreille). 



Telson (cingulum ultimum) coxis perparvulis. Pleopoda (pedes spurii) 

 posteriora nuda, ad telson marginem exteriorem articulata, basis quadri- 

 lateralis ; Ischium trigonum, satis appendiculatum, nudum, lobus acces- 

 sorius triangularis. Antennae intemae 3-articulatae. Antenn. extern, 

 basis rotundatus, non lobatus ; filamentum 3-ai*ticulatum. Abdominis 

 cingulum coxae parvae. Carapacis frons nee mediane nee lateraliter 

 lobatus. 



1. —Philoscia muscorum {Latreille). 



Corpore laeve, nitido, splendido. Fronte paululum medio arcuato. 

 Telson late-triangulari, apice acuminate, lateribus rectis. Pleopodis 

 posterioribus; Ischio, falciformi; Appendice ischii dimidio longitudinera 

 vix superante. 



Sub musco lapidibusque ubique abundantissime, etiam ad littus ma- 

 rinum. 



