140 DK. C. CHILTON ON THE 



Habitat. — Found in great abundance throughout the whole of New Zealand, 

 especially around buildings, in greenhouses, &c. ; rarely in the native bush. 



Remarks. — This species is practically cosmopolitan, being found all over Europe, 

 North Aniei'ica, at the Cape of Good Hope, and Kamtschatka. In Australia it has 

 been recorded from Melbourne and Tasnaania, and I have specioaens from Sydney also. 

 In New Zealand it has hitherto been known under the name JPorcellio graniger, Miers, 

 though Mr. G. M. Thomson suggested some years ago that it was probably a cosmopolitan 

 species, and pointed out how easily it might be spread by artificial means*. Eudde- 

 Lund, in his " Isopoda Terrestria," had previously suggested tliat the New Zealand 

 species was perhaps the same as P. keiils, Latr., but a comparison of specimens has 

 shown that it differs considerably from that cosmopolitan species, but is undoubtedly 

 the same as P. scaber, Latr. 



The variety marmorata, in which the general dorsal surface is lightly coloured and 

 variegated with irregular dark patches, is pretty abundant in New Zealand, and the 

 variety mavghuda " black, with side-plates light yellowish," is also sometimes seen. 

 Some years ago Mr. W. W. Smith sent me a large series of specimens from Ashburton, 

 some of the usual form (variety immaculatu), others of the variety marmorata, and a 

 large number with the whole dorsal surface (in spirit) of a reddish-brown varying from 

 a light yellowish-brown to dark orange-brown, some of them having the side-plates 

 lighter in colour than the centre portion ; there is a similar specimen in Mr. Thomson's 

 collection, and I have occasionally seeu similar specimens from other localities ; in this 

 form the tubercles on the dorsal surface are hardly so well marked as in some of the 

 darker forms belonging to the variety immaculata, but there seems to be considerable 

 variation in the degree of tuberculation in all the varieties. 



Many years ago Brandt described albino and partially albino forms of this species, 

 and gave figures showing all the stages between complete albinos and the ordinary dark- 

 coloru-ed form'^f . 



The great vaiiability in colour of this species has been noted by Eilhol in specimens 

 collected from New Zealand. 



Genus 4. Metoponorthus, Budde-Lund, 1879. 



Metoponorthus, Budde-Lund, Isopoda Terrestria, p. 161 (1885). 

 Metoponorthus, Sars, Crustacea of Norway, ii. p. 183 (1899). 



Generic Characters. — " Body oblong, subdeprcssed, with very thin integuments. 

 Cephalon with the lateral lobes very small, frontal lobe obsolete. Side-plates of meso- 

 some but very slightly promiaent. Metasome abruptly contracted, with the epimeral 

 plates of third to fifth segments sub-appressed ; last segment comparatively short, 

 triangular. Eyes well developed, lateral. Antennuke very small, with the last joint 

 quite short. Autennte slender and elongated, fiagellum biarticulate. Oral parts nearly 

 exactly as in Forceltio. Legs slender, and greatly inci'easing in length posteriorly. 



* "• Proc. Royal Societ)' Tasmania," 1892, p. 4 (.separate copy), 

 t Hor;E Soc. entom. Ross. T. viii. (1871), pp. 167-176, 1872. 



