82 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 



with living in hothouses I have also found in quite open 

 situations. 



These wood-lice do considerable damage to the plants, how- 

 ever, evidently enjoying the food offered by the roots of the 

 young plants, among which I have found them often in clusters. 

 They receive, in consequence, but scanty consideration from the 

 fruit-grower. But they are not always strict vegetarians, and 

 will not hesitate, should the necessity and opportunity arise, to 

 sacrifice some near relation. While keeping a number of in- 

 dividuals of Cylisticus convexus (De Geer) in captivity, I found 

 that they had no scruples in making a meal, occasionally, of 

 some of the weaker members of the family, and once, having 

 occasion to put together in a tube an individual of this species 

 and one of Trichoniscus roseus (Koch), I found, on returning 

 to examine the creatures some time afterwards, that all that 

 remained of the latter was a little bit of his outer coat. 



One fact which struck me while observing these wood-lice in 

 the hothouses and elsewhere was the apparent associating of 

 certain species with others. In some places I found Porcellio 

 dilatatus Brandt, mixing freely with Cylisticus convexus, both 

 species being present in considerable numbers. In a small green- 

 house in Camphill Gardens, Glasgow, I met with some individuals 

 of Trichoniscus pygmaeus, G. O. Sars, and T. pusillus, Brandt, in 

 company with hundreds of T. roseus, and no other wood-lice near. 

 In one hothouse Metoponorihus pruinosus, Brandt, seemed to hold 

 the place to the almost total exclusion of all others. P. dilatatus 

 being found very sparingly inside, though they were in fair 

 numbers in the grounds in the neighbourhood ; while in 

 another hothouse C. convexus was the oYily species in evidence, 

 and there they were present in considerable numbers. In open 

 situations I have found the three species, Oniscus asellus, Lin., 

 Porcellio scaber, Latr., and Cylisticus convexus, generally in 

 company. 



New Records. 



Genus Trichoniscus, Brandt, 1833. 



Trichoniscus pygmaeus, G. O. Sars. — This is one of the smallest 



of the land-isopods, the adult female measuring about 2.1 mm. 



It may be distinguished from all other species of the genus by 



the three-articulate flagellum of the antenna?, by the lateral parts 



