502 



MERISTIC VARIATION. 



[part I. 



Fig. 167. Silpha nigrita, No. 769. Eight middle femur bearing a compounded 

 pair of extra legs, r, ventral surface of nearer extra leg. V, ventral surface of 

 the remoter extra leg. (In Rouen Mus.) 



770. Tenthredo solitaria (Sawfly): tibia of right middle leg divides 

 in peripheral third to form two branches, of which the anterior bears 

 the normal tarsus. The posterior branch arises from the postero-ven- 

 tral surface of the normal and bears a double tarsus consisting of the 

 posterior parts of a pair compounded in Position VP, almost exactly. 

 Tibial spurs as in Fig. 166. The compound tarsus has only 4 joints, the 

 5th being apparently broken off. In Cambridge Univ. Mus., history 

 unknown. 



771. Telephorus rusticus (Malacoderm) : tibia of left middle leg dilated 

 and somewhat deformed in its peripheral portion. It presents two 

 apical processes, the one anterior and the other posterior. The anterior 

 of these bears a normal, backwai^dly directed tarsus, but the posterior 

 process bears two tarsi by separate articulations. The anterior of these 

 two tarsi is directed forwards to face the tarsus of the other apex, but 

 the posterior tarsus is backwardly directed. [From its attitude it is 

 clear that the middle of these tarsi is a structure complementary to one 

 of the others, but there is no evidence to shew whether it is a pair to 

 the anterior or to the posterior. Position either VPP, or DAA, pro- 

 bably the former.] Kuaatz, Dent. ent. Zt,, 1880, p. 344, tig. 33. 



/72. Anthia sp. (Carabidffl): left posterior tibia bearing two supernumerary tarsi. 

 The postero-ventral side of the apex of the tibia is dilated so as to form a triangular 

 projection, causing the point of articulation of the normal tarsus to be raised 

 upwards. The projection bears two tarsi of which the posterior curves downwards 

 and backwards, being fashioned as a left tarsus while the anterior curves forwards 

 and slightly upwards being a right tarsus. These two tarsi have unfortunately been 

 broken but were presumably complete. The whole apex of the tibia bears five spurs 

 instead of two, but the relation of the spurs to the separate tarsi was not clear. The 





