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experiments were made by the work of forty filatures, working 

 four thousand five hundred basins. All our worms in Bengal give 

 us for filature silk several crops of cocoons during tlie year, except 

 a solitary species of annual, origin unknown, and rapidly becom- 

 ing extinct. 



The chief worm is called the Dessie, or as the word implies, 

 country. It supplies nearly all the cocoons of the large November 

 bund, or cold weather crop of Bengal, and yields the finest silk. 



The cocoons are small, and are sometimes called the " chota- 

 poloo," or small worm. The produce of the best quality is about 

 10,500 cocoons to one pound of silk. This worm thrives best in 

 cold weather. The hatching of the egg to the completion of the 

 cocoon of this worm, is about thirty-six days in cold weather, but 

 much less in hot weather. 



The next species is the Madrassie, meaning sea-born. It is 

 sometimes called Nystree. It is produced throughout the year; 

 thrives best in hot weather, from March to September. From 

 hatching to full cocoon, often only twenty-five days. 



The Bozo-polo, or large worm, is an annual; it is, however, 

 failing. These worms mcike 10,000 cocoons ro one pound of silk; 

 while in France, 2,500 cocoons makes the same. 



In 1854, I imported, overland, a large quantity of the best 

 French silk worms' eggs; only 5,000 or 6,000 were good, out of 

 a very large parcel. Some commenced hatching fifteen days after 

 the boxes were opened. Fahrenheit thermometer sixty to seventy 

 degrees, and so on, hatching irregularly, until at noon, Fahrenheit 

 marked one hundred degrees in the house. The Bengal natives 

 were astonished at the warmth of these worms. I crossed the 

 native worm with the French, and the product was equal to the 

 French. But, in 185 6, I found my improved stock, much of it, 

 had reverted to the old annuals. 



The Syrian cocoon is nearly equal to the French. I have not 

 experimented on the wild worm and others, (the Bomby and Hut- 

 toin,) but I believe they can be, some of them, domesticated. 



The Societe Zoologique d' Acclimation (Napoleon's) is producing 

 wonderful changes. Our Bengal operatives in the filatures, get 

 of£ the same amount af cocoons, at least one and a half pounds of 

 silk, where we get but one pound, and at a far less cost than we do, 



