74 CONTENTS OF EACH VOLUME. 
Sessiliventria include the Tenthredinide, Cephide, Siricide, and Orysside, and the 
Petioliventria the Cynipide, Figitide, Chalcidide, Ichneumonide, Braconide, 
Stephanide, Evaniide, Trigonalide, Pelecinide, Proctotrupide, and Chrysidide. 
When Mr. Cameron’s work on these insects was published, in 1883-1888, scarcely any 
Mexican material was available for study, and the numerous Ichneumonide described 
from that country in 1873 by Cresson could not therefore be identified. Mr. H. H. 
Smith subsequently made very extensive collections in Mexico of all the above- 
mentioned families, too late, unfortunately, to be included. Mr. Cameron’s contri- 
bution, therefore, is very incomplete as regards the total number of species inhabiting 
the region, although it adds considerably to our knowledge of these Hymenoptera. 
The numbers of species for the different families are as follows: Tenthredinide 152, 
Cephide 1, Siricide 3, Orysside 2, Cynipide 15, Figitide 9, Chalcidide 121, 
Ichneumonide 533, Braconide 176, Stephanide 5, Evaniide 23, Trigonalide 9, 
Pelecinide 2, Proctotrupide 43, and Chrysidide 19. 
The twenty coloured plates include figures of 451 species. 
34, Hymenoptera. Vol. II.: by P. Cameron: Fossores. 
In this Volume the species belonging to the Section Fossores (the sand- and wood- 
wasps), under which the author includes the Family Mutillide, of the Hymenoptera 
Aculeata, are enumerated; the other Sections are known as Heterogyna (ants), Diplo- 
pterygia (Eumenide and Vespide), and Anthophila (bees). ‘The Fossores, including 
Mutillide, number 711 species, of which 391 are treated as new, the total number 
being: Sphegide 67, Ampulicide 2, Larride 52, Nyssonide 382, Bembecide 26, 
Philanthide 54, Mimeside 8, Pemphredonide 3, Crabronide 24, Pompilide 163, 
Scoliidee 59, Mutillidee 221. The pages 1-400 were published between 1888-1896, 
the rest in 1899 and 1900. Mr. H. H. Smith’s Mexican collections fortunately 
arrived in time to be included, so that the enumeration of the species in Vol. II. is 
more complete than in Vol. I. of the Hymenoptera. In the Introduction (published 
in 1900) there is a classified list of the 312 species figured on the fourteen coloured 
plates. 
35. Hymenoptera. Vol. III.: by Prof. A. Forel: Heterogyna. 
Volume III. of the Hymenoptera, published in 1899-1900, contains an account, in 
French, of the Heterogyna or Ants, numbering 382 species, 66 of which are described 
as new. From the author’s remarks on page 1, it would seem that a large number 
of the Central-American forms are common to South America, and that the Formicid- 
fauna is mainly Neotropical. A few closely related S.-American species are described 
in foot-notes. The four uncoloured plates include figures of 57 species ; plate II. shows 
the nests of various ants among leaves, or in the spines of Erythrina, Acacia, &. A 
considerable number of species have been added to the fauna by Prof. Forel and other 
writers during the past ten years, showing that new forms still await the collector. 
