( Iv ) 



the Director, Mr. H. Bolton. We are indebted to Miss N. M. 

 Ward for the discovery of the specimen. The beetle is a large 

 one, some 30 mm. long, and the affected tarsus is about 4 mm. 

 in length. The malformation is a somewhat unusual one, I am 

 not sure that I have heard of and have not seen a similar one. 

 It has no trace of the extra parts, being as it were represen- 

 tations in a mirror of the original parts, which Prof. Bateson 

 has shown to be so frequent in such specimens. It is, of course, 

 not quite correct, in parts that are duplicated, to call one of 

 the two the original and the other an addition; for it is most 

 usual for both to have an equal claim, or neither to have any, 

 to be called the original normal structures, making the other 

 an addition. In the present specimen, however, it is very 

 tempting, if it be not, indeed, the actual fact, to regard the 



Rough sketch of tarsus ( X 8) from a dorsal but slightly posterior 

 point of view. 



affected as a normal tarsus, with additional fourth and fifth 

 joints springing from the extremity of the third. 



Except for the expansion towards the end of the third joint, 

 to give origin to the abnormal joints, the tarsus I accept as 

 normal appears to be so in all respects. 



The additional joints arise dorsally, so that the abnormal 

 fourth joint lies above the dorsum of the normal fourth, and 

 it has this peculiarity, that it is, as it were dorsal in all its 

 aspects. The normal joint has a number of terminal spines 

 and on its ventral aspect a double set of gold-coloured bristles 

 that are directed inwards, so that the ends of the bristles of 

 each set meet the other in the middle ventral line of the joints. 



The abnormal fourth joint is quite devoid of spines and 

 bristles, and is smooth and rounded in all aspects. It is very 

 little smaller than a normal joint, not apparently more than 

 is due to its end being rounded, instead of being produced 



