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substances, and a number of tracks of annelides. No bird-tracks 

 were discoverable on this surface. 



The stone is dense, from being well charged with oxide of 

 iron, and contains objects of interest which would well bear 

 another examination. 



Mr. C. J. Sprague exhibited a specimen of a Fungus, 

 (IJredo effusa,) growing upon the rose plant in the vicinity 

 of Boston. 



Dr. C. T. Jackson observed, that the fungus was composed of 

 a series of irregularly shaped cells, some globular, and others an- 

 gular, of an orange-red tint. Upon the application of nitric acid, 

 the outer portions of the cells became transparent, whilst in the 

 interior a mass of granules was developed. Caustic potash, on 

 the other hand, made the granules indistinct. 



Dr. Durkee thought the angular form of the cells was due to 

 compression. 



Mr. Sprague thought it might be owing to drying. 



Dr. J. N. Borland gave the following account of the 

 feeding of a large Boa Constrictor, (on exhibition in this 

 city,) measuring about twenty feet in length : — 



The Boa was in a state of considerable activity, looking about 

 him as if for prey. In this condition, a large-sized adult rabbit 

 was introduced into the cage at one o'clock precisely. The rab- 

 bit seemed unconscious of his enemy. The serpent threw back 

 his head and coiled firmly his prehensile tail, remaining fixed in 

 this position, and occasionally emitting a sharp hiss, for three 

 minutes. At this time the rabbit approached the head of the 

 serpent after smelling along his body, when the Boa, with great 

 and sudden violence, threw himself on his victim, seizing the 

 rabbit's head in his mouth, and at the same time coiling his tail 

 around its body. Remaining in this position ten minutes, during 

 which the rabbit was killed, the process of deglutition com- 

 menced. This operation consisted in alternately unhooking first 

 one side and then the other of both upper and lower jaws, insert- 

 ing further along in the body of the rabbit its recurved teeth, and 



