A DECEPTION DETECTED 107 



hensile, thus making six pairs of legs, with a structural 

 arrangement as regards three of them that would be unique 

 among the Brachyura. At each date the species is said 

 to come from the Isle of Guadeloupe. Leach rightly per- 

 ceived that error and confusion were lurking somewhere, 

 if it should not rather be said that they are conspicuous 

 on the face of the two discordant accounts. Milne- 

 Edwards in 1837, though with a confession of great un- 

 certainty, institutes for the single genus Pactolus the tribe of 

 the Pactolieiis, which he places among the Anomura. But 

 soon after, in 1839, de Kaan with great acuteness ob- 

 served, 'Pactolus, Leach, Zoological Miscellanies, vol. ii. 

 tab. 68, seems to me to be made up of the thorax of a 

 female Leptopodm sagittaria, to which the legs of some 

 other animal have been united ; for the thorax of Pactolus, 

 just as also the rostrum and abdomen, agrees with the 

 female Leptopodia. The unlikeness in colour between the 

 legs and the thorax in the figure referred to at once 

 reveals the deception. Never are two alien forms found, 

 agreeing exactly in the thorax, yet so disagreeing in the 

 legs.' The principle here enunciated is worth remembering, 

 as in some parts of the world there are dealers who delight 

 and find profit and have also great skill in fabricating mon- 

 strosities, sometimes such as have deceived the very elect. 



Nearly related to Inachus is the gigantic Macrocheira 

 Kampferi, de Haan, 1839, of which mention has been 

 earlier made. In Japanese it is called the insular crab. 



Huenia is another genus of this family instituted by 

 de Haan in 1839. The name refers to the acutely trian- 

 gular form of the carapace, and is derived from the Greek 

 word VVLS, a ploughshare, a derivation which would have 

 been hard to guess, had not de Haan obligingly mentioned 

 it himself. At the foot of his plate 23 he names the 

 figures ' 4. MAJA (Huenia) elongata n. 5. id. variet. 6. 

 MAJA (Huenia) heraldica n.' But the species established 

 in the text is Mfja (Huenia) proteus. The double generic 

 name results from the inconvenient practice, still some- 

 times followed, of splitting a genus up into sub-genera. 

 Sub-genera, if they are worth anything, are pretty sure to 



