138 PROCEEDINGS OF THE ACADEMY OF [1819. 



other, this adoption of an alien queen is an example of the strong 

 instinct which controls for preservation of the species. 



April 8. 

 The President, Dr. Ruschenberger, in the chair. 

 Thirty-five persons present. 



April 15. 

 The President, Dr. Ruschenberger, in the chair. 

 Thirty-three persons present. 



The following papers were presented for publication: 



" Placenta of Macacus Cynomolgus." By H. C. Chapman, 

 M.D. 



"Description of a new species of Chirocephalus." By John A. 

 R3'der. 



The death of Isaac Hays, M.D-., a member, was announced. 



On Special Fecundity in Plants At the meeting of the Botani- 

 cal Section, Mr. Thomas Meehan exhibited specimens and re- 

 marked on the curious fact that special fecundity was not con- 

 fined to individuals of any one species of plants, but the species 

 themselves often exhibited peculiar fertility, as other species again 

 were characterized b}* an indisposition to produce seed. Occa- 

 sionally whole families or natural orders of plants exhibited these 

 peculiarities. In our green-houses the Begonia, which has male 

 and female flowers separately on the same plant, some species had 

 an unusual preponderance of fertile female flowers; others, as, for 

 instance, Begonia glaucophylla, had never borne a female flower 

 within his observation. The race of Primroses were famous for 

 an apparent abhorrence of their own pollen, rarely producing 

 any seeds unless the plant had the chance to receive pollen from 

 some other plant; but the Madeira Primrose Primula involu- 

 crata was a remarkable self-fertilizer, and every flower, appa- 

 rently under the most varied circumstances, produced an immense 

 quantity of seeds. As illustrations of the infertility of some 

 natural families, Asclepiadise and Apocynaceas were quoted. In 

 these we have the common Hoya or "Wax plant," the Oleander, 

 the common Silk-w r eeds, in which thousands of flow r ers are pro- 

 duced for every one that results in a seed vessel. In this part of 

 the world at least the "Trailing Arbutus" rarely, if ever, pro- 

 duces perfect seed. 



