392 Dr. Henry Woochcard — Coal-Measure Crustaceans 



altitude of 4,000 feet, on Mount Wellington in Tasmania.^ The very 

 striking peculiarities of the animal, the absence of a carapace, the 

 presence of plate-like gills attached to the bases of the thoracic legs, 

 and the possession of an auditory organ in the pendunclo of the 

 antennules, led Thomson to regard it as the type of a new family of 

 Schizopods, the Anaspidse, while suggesting that it might be entitled 

 to even higher specific rank.- Fresh specimens of Anaspidps having 

 come into Dr. Caiman's hands, when studying at the Museum of 

 University College, Dundee, he was enabled to add some important 

 points to Mr. Thomson's previously published account of the external 

 anatomy of the animal, and to compare it with some already described 

 fossil forms. This he has done in an admirable memoir communicated 

 to the Eoyal Society of Edinburgh in 1896,^ from which we venture 

 to make some extracts. 



Anaspides TASMAN^iiE, G. M. Thomson, 1896. 



Dr. Caiman points out that Thomson (in his original description) 

 attributes to this Crustacean the possession of eight free thoracic 

 segments, but Caiman shows that the first of these is not actuall}^ 

 a separate segment, being a part of the head, the supposed division 

 being in reality only a superficial groove in the integument, corre- 

 sponding no doubt to the " cervical sulcus," which in the Mysidse 

 crosses the carapace immediately above the mandibles, and he 

 accordingly identifies it with this sulcus. It is also homologous with 

 the cervical groove in the Decapods, behind which the segments 

 bearing the two pairs of maxillae would morphologically be placed. 



Fig. 9. — Anaspides tasmanicB, G. M. Thomson (living), from freshwater pools 

 4,000 feet above the sea, on Mount "Wellington, Tasmania, c.gr. = cephalic 

 groove; ii-viii, the seven free thoracic segments; 1-6, the six abdominal 

 segments ; the seventh is the ' telson ' or tail-spine. Drawn from a specimen in 

 the British Museum (Nat. Hist.) under Dr. Caiman's direction. (All the 

 figures have been drawn from nature by Miss G. M. Woodward, except 

 Figs. 6, 7, and 8, which were copied by her from Dr. Packard's restorations.) 



1 Mr. G. M. Thomson has since added another locality, namely, "Lake Field," 

 a spot forty miles from Hobart Town, Tasmania, also at an elevation of about 

 4,000 feet above the sea (Trans, floy. Soc, 1897, op. cit., p. 802). 



2 Trans. Koy. Soc. Edinb., vol. xxxviii (1897), pt. iv, pp. 787-802. 4to. 



