554 Lrecent Literature. [July, 
are to be inferred from the condition of these organs in the adult, 
and thus enable us to better understand the homology between 
the Cephalopod and a typical Mollusk than before, as first shown 
Grenacher, while Professor Brooks has discovered several 
additional stages which enable him to correct some of Grenacher’s 
conclusions and to fill up the gaps in the evidence bearing on this 
subject. The yolk sac Professor Brooks regards as the homologue 
of the gasteropod foot; the arms of the Cephalopods have no 
homologues in the Gasteropods, but may, perhaps, be the equiva- 
lents of the “cephaloconi” of the Pteropod, Clio; Brooks also 
believes that the siphon is a structure peculiar to the Cephalopods, 
with no equivalent in the Gasteropods. The views of Huxley, 
Grenacher and Von Ihering are presented, with the author’s rea- 
sons for agreeing with or dissenting from them. 
SEconD Report OF THE U. S. EnromotocicaL Commission. — 
This volume of four hundred pages gives the results of the labors 
of the Commission during the years 1878 and 1879. It is divided 
into fourteen chapters, of which the most are of a practical nature 
relating to the following subjects: Additions to the chronology of 
locust ravages ; the relation of the locust and its ravages to agri- 
culture and the settlement of the Territories; facts concerning 
and laws governing the migrations of locusts in all countries; 
habits and characteristics of locusts in all countries within the 
while the appendix contains the description of a number of new — 
species of grasshoppers collected by the Commission in the West, 
cheba by Mr. S. H. Scudder, and illustrated with a lithographic 
ate. 
| Department of the Interior. Second Report of the U. S. Entomological eaereore 
sion for the years 1878 and 1879, relating to the Rocky Mountain Locust and the 
manent breeding grounds, with a view of preventing its migrations into the whe 
i ntry, in pursuance of SDP ee 
made by Congress for the purpose, with maps and illustrations. CHARLES V. RI r . 
A. S. PACKARD, JR., and Cyrus THomas, Commissioners. Washington, 1880. ite 
