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TRANSACTIONS OF SECTION D. 1065 
7. On the Echinoderm Fauna of the Island of Ceylon. 
By Professor F. Jerrrey Bert, M.A., Sec.h.M.S. 
The author gives an account of the remarkable advance in our knowledge of the 
Echinoderm fauna of the island of Ceylon. ‘Till 1882 some four species were 
known from the island; forty-five are now known, and some six Holothurians 
remain to be investigated. These advances are due partly to the collection of Pro- 
fessor Haeckel, but chiefly to the industry and activity of Dr. W. C. Ondaatje. 
MONDAY, SEPTEMBER 14. 
The following Report and Papers were read :— 
1. Report on the Aid given by the Dominion Government and the Govern- 
ment of the United States to the encouragement of Fisheries, and to the 
investigation of the various forms of Marine Life on the coasts and rivers 
of North America.—See Reports, p. 479. 
2. On the Size of the Brain in Extinct Animals. 
By Professor O. C. Marsu. 
The main points were the following :— 
1. All Tertiary mammals had small brains. 
2. There was a gradual increase in the size of the brain during this period. 
‘3. This increase was confined mainly to the cerebral hemispheres, or higher 
portion of the brain. 
4, In some groups, the conyolutions of the brain have gradually become more 
complex. 
_ 5. In some, the cerebellum and the olfactory lobes have even diminished in 
size. 
6. There is now evidence that the same general law of brain growth holds 
good for birds and reptiles trom the Jurassic period to the present time. 
To these may be added the following :— 
7. The brain of an animal belonging to a vigorous race fitted for a long 
survival is larger than the average brain of that period in the same group. 
8. The brain of a mammal of a declining race is smaller than the average brain 
of its contemporaries of the same group. 
This question is more fully discussed in the author's monograph on the 
‘ Dinocerata,’ just published by the United States Geological Survey. 
3. On the Systematic Position of the Chameleon, and its Affinities with the 
Dinosauria. By Professor D’Arcy W. THompson. 
4. On the Hind Limb of Ichthyosaurus, and on the Morphology of Vertebrate 
Appendages. By Professor D’Arcy W. THompson. 
A skeleton ascribed to Ichthyosaurus platyodon in the Anatomical Museum of 
Edinburgh University exhibits certain remarkable peculiarities in the hind-limb, 
which perhaps render it the most primitive limb known in vertebrates above 
fishes. 
In the first place, the femur has articulated with it three bones, identifiable as 
tibia, intermedium, and fibula, as in Marsh’s Sauranodon, and as in the limb 
