462 MR WALTER E. COLLIN GE ON 



1-3 short, 4th with groove on the outer side, the 5th being the longest ; flagellum 

 two-jointed, with terminal style. Oral appendages typical. The segments of the 

 mesosome are convex dorsally and roughly tuberculate, with moderately developed 

 pleural plates, the first of which partly surrounds the cephalon ; posterior angles 

 acutely produced backwards. Thoracic appendages long, otherwise typical. 

 Uropoda (figs. 3-5) extending considerably beyond the telson, basal plate grooved 

 on the outer side ; exopodite long, lanceolate, and slightly curved upwards, setaceous ; 

 endopodite short, slightly longer than the basal plate and telson, terminating in 

 four stout spines and a long style, setaceous. Telson (fig. 3) with broad anterior 

 portion, terminating posteriorly in a long, blunt point, slightly grooved dorsally. 



Length 17 mm. 



Colour (in alcohol) blackish with a tinge of olive-green. 



Habitat. — S. Spain. Easter 1894 (W. Bateson). 



Type. — In the Cambridge University Museum of Zoology. 



This interesting species finds its nearest ally in P. nicMesi, Dollfus, from which, 

 however, it is separated by the form of the lateral lobes of the cephalon, the 

 antennae,. the uropoda, and the telson. In the form of the cephalon it bears, at first 

 sight, a superficial resemblance to P. magnificus, Dollfus, but is very distinct 

 from that species when examined in detail. 



I have much pleasure in associating with this fine species the name of Professor 

 W. Bateson, F.R.S., to whom the University is indebted for the specimens. 



2. Porcellio explanatus, n. sp. (PI. I, figs. 7-11.) 



Body large, broadly oval, sparsely tuberculate, dorsal face somewhat flattened. 

 Cephalon (fig. 7) with well-developed lateral lobes, deflected downwards ; median 

 lobe a narrow ridge between the two lateral lobes ; epistoma convex. Eyes 

 moderate in size, situated dorso-laterally. Antennulse short and stout. Antennse 

 (fig. 8) covered with minute setae, joints 1-3 short, 3rd joint with tooth-like 

 process on the outer side, 4th joint with groove on the outer side, the 5th being the 

 longest ; flagellum two-jointed, with terminal style. The segments of the mesosome 

 are somewhat flattened, sparsely tuberculate, with moderately developed pleural 

 plates, the first of which partly surrounds the cephalon, the posterior angles slightly 

 produced backwards. Uropoda (figs. 9-11) extending beyond the telson, setaceous, 

 basal plate almost cubical and deeply grooved on the outer side ; exopodite broad, 

 lanceolate, biconvex, with slightly raised median ridge ; endopodite short, slightly 

 longer than the basal plate and telson, and produced into a ridge on the ventral 

 side, terminally there is a short style. Telson (fig. 9) anteriorly more triangular 

 than in P. batesoni, terminating posteriorly in a long acute point, with slight dorsal 

 groove. 



Length 20 x 10 mm. 



