IIYATT: REPORT OF THE CURATOR. 
109 
Dynamical Zoology. 
The Curator lias been working upon this collection more or less, 
but has not succeeded in making any noteworthy additions. Dr. 
C. S. Minot has, however, sent the first guinea-pig of a series he 
proposes to give us, showing the laws of growth and heredity. 
Geology. 
During the summer and autumn Professor Crosby was engaged 
in the investigation of the geology of the Boston Basin. The third 
part, on the Blue Hills complex, or the area between Weymouth 
Back River and the Neponset River, embracing the Blue Hills proper 
and portions of Milton, Quincy, Braintree, and Weymouth, is about 
ready for publication. It will be accompanied by a good series of 
maps and other illustrations. The publication of the third part has 
been purposely delayed in order to take advantage for the purpose 
of illustration of the very complete and elaborate topographic map 
of the Blue Hills Reservation, which has been executed during the 
past year for the Metropolitan Park Commission. This map is now 
finished, and the Commission has not only authorized its early 
publication by the Society, but is sharing with the Society the cost 
of its reduction from the original sheets. 
The third part of this investigation of the geology of the Boston 
Basin is, in various ways, the most important of the entire series; 
for we have in the Blue Ilills complex a key to the geology of the 
whole Cambro-Carboniferous area of eastern Massachusetts. The 
geology of any other equal area could be more safely neglected than 
this one; and the correlation and other problems of the complex 
being now approximately determined, the remainder of the work on 
the Boston Basin can go forward more rapidly. 
Among the more important results of the later field work is the 
clear proof of the existence in the Cambrian slates of a whole series 
of diabase dikes antedating the eruption of the granite and felsite. 
Mr. Theodore G. White has reexamined with Professor Crosby the 
localities of special petrographic interest, and he will contribute to 
this part of the work. Mr. A. W. Grabau will prepare for this work 
a complete account of the paleontology of the Cambrian strata of the 
Boston Basin, so far as it is known. In this connection it may be 
