64 CONTENTS OF EACH VOLUME. 
the birds, many genera of which are represented by distinct species on each side of a 
line which he is inclined to place north of the Nicaraguan lakes and their outfall, the 
Rio San Juan ?” 
‘The thirteen coloured plates include figures of 324 species. 
Mr. Bates subsequently wrote two papers on the Mexican materia] received from our 
collectors afier the present Volume was closed :— 
(1) ‘ Additions to the Cicindelide Fauna of Mexico’ (Trans. Ent. Soc. Lond. 
1890, pp. 4938-510, pl. 16). 
(2) ‘Additions to the Carabideous Fauna of Mexico’ (op. cit. 1891, pp. 223- 
277, pls. 18, 14). 
16. Cotzoprera. Vol. I. part 2: by D. Sharp: Haliplide, Dytiscide, Gyrinide, 
Hydrophilide, Heteroceride, Parnide, Georisside, Cyathoceride, and 
Staphylinide. 
For these nine families of Coleoptera 1790 species are enumerated, 1405 of which 
belong to Staphylinide, 168 to Dytiscide, and 141 to Hydrophilide, the others being 
of limited extent. The author, in his ‘Introduction’ (published in 1887), states that 
the water beetles (Dytiscide) are apparently subject to different laws of distribution 
from other Coleoptera, illustrating in this respect what he believes to be the case 
with aquatic organisms generally, viz. diminished endemicity, and therefore but little 
adapted for consideration in questions of zoo-geography. The study of the exotic 
Staphylinide appears to be practically in its infancy, and but little can be done in the 
way of comparison with the fauna of other tropical regions. In the case of genera 
with a large number of species and a wide distribution, the Central American 
Staphylinids are stated to be much more nearly allied to those of South than to 
those of North America. Dr. Sharp is therefore inclined to agree with the opinion 
expressed by Bates that the fauna of the region under investigation is essentially 
Neotropical. The Staphylinide first brought from the tropics included an undue 
proportion of comparatively large, bizarre, or brilliantly coloured forms, but it is clear 
that this was chiefly due to imperfect collecting. Indeed, one of the striking facts in 
connection with the material brought together by the Editors is the very large number 
of minute and obscure insects, so that it can scarcely be said that the Central American 
Staphylinide are, on the average, larger or more brilliant than those of Europe. 
Of the nineteen coloured plates, fourteen are devoted to Staphylinide, 445 species 
being figured altogether. 
17. Cotroptera. Vol. II. part 1: by Dr. Sharp, A. Matthews, and G. Lewis: 
Pselaphide—Byrrhide. 
The twenty-two families enumerated in this volume are collectively termed 
Clavicornia by various authors, and in recent catalogues of Coleoptera the Erotylide, 
