FROM THE society's GARDE^'S. 663 



or proximal half of the mesosome is large ; the two forwardly- 

 directed spines are present, one on each side at its posterior 

 end ; while the distal or telomeral half, strongly chitinised, 

 is telescoped up within the endomeral. Similarly with another 

 new species from Abdimia abdimii (Licht.). 



Comparison ivith the Apparatus of Neophilopterus tricolor 

 (text-fig. 14). — This apparatus, while resembling the preceding 

 in its basal plate and parameres, differs from each of the three 

 forms mentioned above in featui'es of the mesosome and in the 

 presence of a small process or plate at the base of the mesosome 

 which I regard as an upper endomeral chitinisation. The part 

 marked Pen., apparently telomeral, is white and more or less 

 membranous, and appears to be held by the basal endomeral 

 portion shaped something like a. pair of pincers. 



The Eecej)tacidum Seminls of the Female of N. incompletus 

 (text-fig. 21 (3), p. 672). — This should be compared with the 

 receptacidum of Ibidoecus (text-fig. 21 (1 & 2)). From a minute 

 opening into the genital cavity, a delicate narrow duct runs up 

 to a large semicircular sac borne upon a short circular calyx, 

 brown in colour, with its rounded outer surface longitudinally 

 striate. 



Mouth-parts of N. tricolor and, N. incompletus. — It is worthy 

 of record that, while the lyiiform organ and basal pieces of 

 N. incompletus are normal, in N. tricolor the same parts are 

 greatly modified. The lyriform organ resembles that of Ibidmcus 

 platalece. Refei'ence to the isolated moditicatioft of the isopogo- 

 metric apparatus in species of certain genera is referred to in 

 Part I. of this paper (p. 273), and is again discussed further on, 

 where the genus Ibklcecus is discussed. 



Ibidcecus, gen. nov. 



Heail with a double signature, consisting of two oblong plates, 

 each plate usually with a small embossed area on the posterior 

 end, which runs out into an angle. Olypeal bands very well 

 marked ; behind, they pass beneath each signatural plate and 

 inwards to be attached to the skull. Antennse long, with an 

 especially long second segment. Abdomen large, broad, with 

 a lateral tergite on each side of each segment, so as to leave 

 a clear median area. A single row of hairs across the tergum 

 of each segment. 



Genotype: Ibidoecus platalece Denny (8, p. 100), 



The type of Denny's species is in the British Museum. 



The following species can certainly be referred to the new 

 genus : — /. Mans G., /. bisignatits IST., /. longiclypeatus Piaget, 

 and /. bimaculatus Mjob. 



The collection of the British Museum contains several un- 

 described species, including one from that interesting South- 

 American bird, Aramus scolopaceus. 



N'eojyhiloj^terus and Ibidoecus appear to be related rather closely. 



