190 PROCEEDINGS OF THE AMERICAN ACADEMY 



the top budders (Asteroids), while those that bud laterally 

 (the Caryophyllians) rank lowest. This order of arrangement 

 corresponds in general to the geological succession of Polypi 

 from the lowest formations upward. Again, every coral reef 

 rising from the bottom of the ocean shows in its various 

 stages a succession of species reminding us of the same gen- 

 eral plan. 



Professor Agassiz remarked, that the study of this class of 

 animals is greatly embarrassed by difficulties growing out of 

 the fact, that the general features vary much in communities 

 of the same species, so that these features cannot be so much 

 depended upon for characters as the intimate structure of the 

 individual polyps. He was inclined to believe that many of 

 the genera of this class recently described by naturalists are 

 based on evanescent characters, in fact upon different stages 

 of development of well-known types. 



Dr. A. A. Hayes called the attention of the Academy to 

 a new species of wax, a specimen of which was on the table, 

 and made the following remarks : — 



" The commercial relations of our country, extending along the 

 rivers of South America, are making known to us the products of the 

 vast forests of the interior, many of which have a high value in the 

 arts and are new to commerce. Among specimens received by me 

 is the peculiar wax before us, respecting the origin of which I possess 

 only a meagre amount of information. ' It is obtained by boiling the 

 deep green leaves of a shrub resembling laurel, abounding in the 

 forests back from Para and Bahia, and is used to some extent as a sub- 

 stitute for wax in the manufacture of candles.' 



" This wax has a light tint of greenish-yellow color, transmitting 

 nearly white light through thin portions ; it is hard, the angles of the 

 fragments scratching gypsum. Its fracture is slightly conchoidal, 

 lustre more dull than that of ordinary wax. By rubbing, it becomes 

 electrically excited, and takes and retains a fine polish ; it is brittle, 

 without softening when compressed between the fingers. 



" The average sp. gr., determined on many specimens, is at 60° 

 F. 1.000, or the same as distilled water. When heated to 120° F. 

 for some time, it loses moisture, and exhales a pleasant balsamic odor, 

 not unlike that of pinks. 



