237 



It had been a question whether the Diurnal or the Nocturnal 

 Butterflies should stand firet in the scale. He proceeded to 

 show that the different positions and relations of the wing in the 

 progress of development of Papilio correspond to the permanent 

 conditions of these appendages in the various families of Lepi- 

 doptera, and thence deduced their true position; placing, 1st, 

 Papilionidse ; 2d, Hesperidae ; 3d, Sphingidoe ; 4th, Bombycidse ; 

 5th, NoctuidfE ; 6th, Pyralidse ; 7th, Tineidee. In a similar 

 way Prof. Agassiz indicated the true position of the different 

 types of Articulata, showing a close analogy between their per- 

 manent forms and the transient conditions of an insect, begin- 

 ning with the caterpillar, which corresponds in type with the 

 Annelida. By the same test he showed the true position of 

 ]\Iillipedes and Spiders; the former being insects with a worm- 

 like form, the latter with the anterior parts united into a cephalo- 

 thorax like the Crustacea, corresponding to the pupa condition 

 in type. 



Dr. Kneeland read a paper entitled, ^' The Manatus not 

 a Cetacean but a Pachyderm." It contained an elaborate 

 and careful analysis and comparison of the skeleton of the 

 Manatus recently presented to the Society with the skele- 

 tons of Cetacea and Pachyderms, showing a much closer 

 analogy with the latter than the former. 



Prof. Agassiz referred to the breathing organs of Mollusks, 

 and remarked that they do not properly correspond to the gills 

 in Crustacea. Thus in the Mollusk they are folds of the body on 

 the inner surface of the mantle, while in the Articulata they are 

 appendages to the legs; so that the plan on which the pulmo- 

 nary apparatus of mollusks is constructed is quite different from 

 that exhibited in other animals. He illustrated his views by 

 descriptions of the various families of this class, showing that 

 the so-called lungs of pulmonated mollusks are in their charac- 

 ter analogous to the respiratory organs of other mollusks, the 

 difference being merely morphological. 



The skeleton of a Javan Squirrel, Sciurus bicolor, was 

 presented in the name of R. B. Forbes, Jr. The thanks of 

 the Society were voted for the donation. 



