oOQ [November, 



small, less known species, M. Tournicri Emery, M. Jiumerosa, Rosenh., 

 and M. pulchelln, Muls , all belonging to his section Tolida, be 

 observed similar but less pronounced sexual characters of this kind, 

 and particularly notices the malleiform apical joint of the male. 

 Thomson (Skand. Col., vi, p. 295) notices a sexual difference in the 

 palpi, but, as will be seen from the accompanying figures, his descrip- 

 tion is incorrect and misleading as regards both sexes : of the male he 

 states, " palpis maxillaribus articulo ultimo securiformi," of the female, 

 " palpis maxillaribus articulo ultimo oblongo subsecuriformi ;" he 

 mentions, however, that the exterior margin of the joint is excavate 

 in the male. Jacquelin-Duval (Gen. Col. Europ., iii, pp. 405, 406, 

 t. 90) describes and figures the trophi of Tomoxia, Mordella, &c., but 

 be says nothing about MordelUstena ; Lacordaire, also (Gen. Col. v, 

 p. Gil), omits all reference to these sexual characters. Curtis, Brit. 

 Ent., ii. Col. ii, figures the mouth-parts, &c., of M. ahdominaUs, and 

 also the insect itself, on t. 4SB, but the apical joint of the maxillary 

 palpi (which he descinbes as large, ovate, hatch et-sbaped) is incorrectly 

 drawn ; his figures and description refer to the female sex only, though 

 be was unaware of the fact. Fowler (Col. Brit., v, pp. 70, 71), not 

 having examples of both sexes of M. ahdominaUs before him for 

 examination, has taken his characters from Thomson. The species 

 itself is somewhat rare in Britain, but I have taken examples of both 

 sexes occasionally on TJmbeUifera; in early summer, at Caterham and 

 Mickleham in [Surrey, and at Darenth Wood and 8trood in Kent ; the 

 male is very mucb rarer than the female. As is well known, the 

 sexes differ considerably in colour, the male having been described 

 by Eabricius under the name of M. ventralis, and the female by the 

 same author as 31. abdominalis. 



I have recently described (Biol. Ceutr.-Am., Col., iv, 2, pp. 310, 

 311) three species of MordelUstena, of large size, from Central 

 America, M. epliippiata, M. UneatocoUis, and M. cequinoctiaUs, with 

 the palpi formed in both sexes as in M. ahdominaUs, Fabr. ; and also 

 several small species, M. imlpaUs, M. perexigua, &c. {op. cit., pp. 347, 

 348), with the palpi as in the above-mentioned South European forms 

 included in ToUda by Emery. In the other British species of Mor- 

 deUistena, the apical joint of the maxillary palpi is not very dissimilar 

 in form in the two sexes, it being, at most, a little longer and more 

 triansrular in the male than in the female ; the section ToUda is not 

 represented in Britain. 



11, Caldervalc Koad, Clapliani Common, S.W. : 

 October 1st, 1891. 



