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looking Crustacean. The female has the chelae of normal size 

 and form, and is altogether a more presentable object than the 

 male: so much so in fact that the two sexes have in more than one 

 instance been described as belonging to two quite distinct species. 

 I have found the females rather more plentiful than the males, 

 as Prof. Sars states to be the case in Norway. Both sexes are very 

 sluggish in their habits and are by no means difficult to capture. 

 If mud containing these Isopods be put in a bowl of sea-water 

 and stirred up they will be found in dozens floating on the surface 

 film almost without movement and may easily be picked out with 

 a brush or pipette. It is impossible to describe the habits of an 

 animal which does not possess any, but it may be stated that 

 Heterotanais Oerstedi so fas exerts itself in its native haunts as to 

 burrow in the mud. The young emerge at the beginning of August 

 and appear to be quite as lazy as their parents, though at that time 

 of year such a disposition is more or less excusable. My identifica- 

 tion of my specimens was confirmed by the Rev. T. R. R. 

 Stebbing, the well-know author of several famous works on the 

 Crustacea. A very closely allied species, Heterotanais Gurneyi 

 (Norman) has been recorded by Mr. R. Gurney from the coast of 

 Norfolk : both appear to be essentially brackish-water species. 



In addition to this Isopod two other very interesting members 

 of the Order are to be found in Christchurch Harbour, each of 

 which has been recorded from only two other localities in the 

 British Isles. The first of these is Cyathura carinata (Kroyer), a 

 slender, almost worm-like, creature about three-quarters of an 

 inch, or 18 mm., in length, and of a whitish colour, marked along 

 the back with brown. It belongs to the family Anthuridae, so called 

 from the " flower-like " appearance of their tails, which are partly 

 covered by the overarching uropods, from which feature also arises 

 the name Cyathura, " cup-tailed." This Isopod, although very 

 rare in this country, is well-known to students on account of the 

 work done on its anatomy by German scientists, though, strange 

 to say, no proper description of the male appears to have been 

 published. Cyathura is remarkable as 1 being the only Isopod, with 

 the exception of the closely related Anthura gracilis (Montagu), 

 which possesses statocysts, and a well-known paper giving a 

 detailed description of these structures has been written by Prof. 

 Thienemann, who has, however, confused this species with 

 Anthura gracilis. The statocysts, a pair of which, each containing 

 a single statolith, are situated in the anterior part of the telson or 

 tail, are, presumably, for the purpose of showing the direction of 

 the force of gravity, but they seem rather out of place in a species 

 which, although of fairly active habits, spends its life burrowing 

 in the mud and is very rarely seen swimming. No explanation of 

 their occurrence in this particular species has so far been brought 

 forward, and it is only by a long and painstaking study of its 

 habits that we can hope to solve the oroblem. Strange to sav its 

 mode of life is in almost every way different from that of Anthura 

 gracilis, the other species possessing statocysts. The female of 



