Insects. 2077 



and although I have never made any experiments with this species, yet I have fre- 

 quently lost the larvae of others in a similar manner. I have always thought that my 

 failures were caused by the caterpillars having been attacked by a parasitical fungus, 

 and my opinion is confirmed by a Report made to the Entomological Society of 

 France,* on the investigations into the nature of the muscardine affecting the silk-worm, 

 by M. Guerin-Meneville, who had been requested by the Minister of Agriculture and 

 Commerce to apply his entomological knowledge to the subject, in order if possible to 

 discover a remedy for the disease. Of this Report I subjoin an epitome. The true 

 nature of the muscardine became known by the memoirs of Messrs. Audouin, Turpin 

 and Boisduval. It is a fungus developed in the parenchyma and cellular tissue of the 

 caterpillar. It spreads with such great rapidity that its progress is sometimes visible 

 to the eye : it is contagious and epidemic, and always fatal. It is not confined to the 

 silk-worm, nor to caterpillars reared in confinement, but has been observed in many at 

 liberty. It is almost always after the last moult, and about the time they are ready to 

 change to pupae, that the caterpillars become affected. Sometimes, in different species 

 of larvae, it presents a different appearance, though it is believed there is really but 

 one species of it; but one constant character has always been observed, namely, that 

 caterpillars which have died from this cause become very dry and brittle, and a very 

 slight pressure will break them into pieces, when the interior of the body appears 

 whitish, powdery and mouldy. It has always been found to exist in greatest abun- 

 dance when large numbers of caterpillars have been placed in a small space, and it is 

 thought that the vitiation of the atmosphere by their excrements has been a fertile 

 source of its appearance and extension. The curative means to be adopted are not 

 given. This account does not agree exactly with that of Mr. Turner, for he says that 

 his caterpillars " turned almost black, the intestines seemed to decompose, and they 

 hung like little bags of fluid ; " neither does he say that they afterwards became dry 

 and brittle. With these exceptions, the symptoms he details seem to agree with those 

 of the muscardine, and I believe that this or an analogous disease caused the death 

 of such of his caterpillars as attained their full growth. In conclusion, I hazard an 

 opinion that to this disease is owing the scarcity of many species of our Lepidoptera. 

 — /. W. Douglas; 19, Nelson Square, Pechham, March 1, 1848. 



Occurrence of Nyssia hispidaria in abundance near Huddersfield. — I have captured 

 during the last two days about seventy specimens of Nyssia hispidaria, upon the stems 

 of oak trees. Most of the trees which I got them upon were covered with lichen and 

 moss. I found the greater part of them about five o'clock in the evening. — John Col- 

 lins ; Kirkburton, Huddersjield, February 26, 1848. 



Remarks on the Apterous Females of our British Geometrce. — Though we find that 

 some two or three of the late autumnal Geometrae have apterous females, the great 

 bulk of them make their appearance during the winter and early spring. The reason 

 of their being so restricted in their powers of locomotion may probably find its solution 

 in the less erratic flight of their mates, whose movements at the fall and opening of 

 the year are necessarily more sluggish than we observe to be the case with those spe- 

 cies that appear during the warm evenings of May and June. The females of the 

 Hiberniae generally are apterous, or partially so. Of the group, progemmaria has the 

 rudimental wings the most conspicuous ; they vary as much in tint as in size, presenting 



* ' Annales de la Societe Entomologique de France,' 1847, tome v. bulletin p. lxv. 

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