Th: Jefferson returns his thanks to Doctors Mitchell and Pascalis for the attention with which they have honored him by the notification in their letter of Apr. 28. of the purpose of the Linnæan society to commemorate the birth of the great founder of that school by a fete Botanique on the 24th instant. he regrets that he cannot join them physically on the occasion, but will certainly be with them in spirit. he will invite also some amateurs in natural science in his own neighborhood to fraternise on the same day with their brethren of New York by corresponding libations to the great apostle of nature, not forgetting the healths of our absent friends. he salutes Doctors Mitchell & Pascalis with sentiments of the highes respect & esteem.