SECT. III. SPECIFIC EXAMPLES. 



upon the longitudinal section of the ovary. The 

 nucleus was not easily separated from the pericarp 

 without injuring it, but its surface was seen to con- 

 sist of a net-work of fibres, being the ramifications, 

 no doubt, of the umbilical cord. 



On the 17th, the nucleus was found to be separa- 

 ble from the pericarp. Its form was egg-shaped, 

 its colour was white, and its surface was marked 

 with a scar towards the upper extremity where it 

 had been detached from the umbilical cord. Upon 

 dissection it was still found to consist of a net-like 

 cuticle, and a pulpy, colourless, and transparent 

 mass contained within it. The cuticle is no doubt 

 the testa of Gsertner, or secundina exterior of Mai- 

 pighi, and the contained substance the chorion. 



On the J 8th, there began to be formed on the inner 

 surface of the pericarp a sort of fibrous substance, 

 or rather a net-like plexus of fibres immediately in- 

 vesting the nucleus. This was the commencement 

 of the formation of the pyrena. The cup, stamens, 

 and pistil, had now fallen. 



On the IQth, the pyrena had acquired a consider- 

 able degree of compactness, and was in some indivi- 

 duals distinguishable from the rest of the parts on the 

 horizontal section, which now exhibited four dis- 

 tinct and concentric circles ; the first and interior 

 circle being the line bounding the gelatinous mass 

 of the chorlon which occupied the centre ; the 

 second being the coats of the nucleus^ which were 



379 



