526  Reviews—Prof. P. M. Duncan’s Indian Fossil Corals. 
grooves (Odontolee), and is represented by the genus Hesperornis. 
The other contains small birds. endowed with great powers of flight, 
and having teeth in sockets (Odontotorme), and biconcave vertebrae ; 
a type best illustrated by the genus Ichthyornis. Other characters, 
scarcely less important, appear in each group, and we have thus a 
vivid picture of two primitive forms of bird structure, as unexpected 
as they are suggestive. A comparison of these two forms with each 
other, and with some recent birds, promises to clear away many diffi- 
culties in the genealogy of this class, now a closed type; and hence 
they are well worthy of the detailed description and full illustration 
here devoted to them. 
The fossil birds now known from the Cretaceous deposits of this 
country are included in nine genera, and twenty species. These 
have all been deseribed by the writer, and are represented at present 
by the remains of about one hundred and fifty different individuals. 
There is evidence of a rich and varied Avian fauna in North America 
during Mesozoic time, and likewise it indicates what may be expected 
from future discoveries. 
We heartily thank Prof. Marsh for this grand work, and shall 
look forward with great pleasure to the issue of the succeeding 
volumes of the Peabody Memoirs on the extinct Pteranodontia, the 
Sauropoda, the Sauranodontia ; the Dinocerata, the Tillodontia, and 
the ancestors of our living Horse. 
TI.—A MonocrarH or THE Fossin Corants anD ALCYONARIA OF 
Stnp. Collected by the Geological Survey of India. By P. M. 
Duncan, M.B. (Lond.), F.R.S. (London: Taylor & Francis, 
1880.) 
N their great work on the Nummulitic Group of India (1858), 
MM. d’Archiac and J. Haime fully described and figured a 
series of fossil corals from Sind, but their stratigraphical position 
and localities were not strictly determined, and they were merely 
referred to the Nummulitic formation, of the Hala Mountains. 
Prof. Duncan re-examined this collection in 1863, and published 
the results in the Journal of the Geological Society (1864), and 
described the new species in the Annals of Natural History for the 
same year. The collection forming the subject of the present 
Monograph is due to the labours of Messrs. W. T. Blanford and 
Fedden, who have carefully recorded the geological position and 
localities from whence the specimens were obtained, so that we are 
now furnished with clear descriptions of the species from the coral- 
bearing series of Sind, and their relations to the representative forms 
elsewhere—a comparison which the author’s previous researches 
have enabled him more readily to make. 
The classification followed in the Monograph is principally that 
adopted by M. Edwards and J. Haime with some modifications, the 
result of the experience of zoophytologists since that book was 
published. The larger number of the 186 species of corals de- 
scribed belong to the Madreporaria-aporosa, and the rest to the 
Madreporaria-perforata. 
