8o The Natural History 



drying : these eggs produce maggots called jumpers, 

 which, harbouring in the gammons and best parts of the 

 hogs, eat down to the bone, and make great waste. This 

 fly I suspect to be a variety of the inusca piitris of 

 Linnaeus : it is to be seen in the summer in the farm- 

 kitchens on the bacon-racks and about the mantelpieces, 

 and on the ceilings. 



The insect that infests turnips and many crops in the 

 garden (destroying often whole fields while in their seed- 

 ling leaves) is an animal that wants to be better known. 

 The country people here call it the turnip-fly and black 

 dolphin ; but I know it to be one of the cokoptera ; the 

 '''' chrysotiiela oleracea, saltatoria, femoribus paslicis crassis- 

 simis.^* In very hot summers they abound to an amazing 

 degree, and as you walk in a field or in a garden, make 

 a pattering like rain, by jumping on the leaves of the 

 turnips or cabbages. 



There is an oestrus^ known in these parts to every 

 ploughboy ; which, because it is omitted by Linnaeus, 

 is also passed over by late writers, and that is the curvi- 

 ^auda of old Moufet, mentioned by Derham in his 

 Physico-theology^ p. 250 : an insect worthy of remark for 

 depositing its eggs as it flies in so dexterous a manner on 

 the single hairs of the legs and flanks of grass-horses. 

 But then Derham is mistaken when he advances that 

 this oestrus is the parent of that wonderful star-tailed 

 maggot which he mentions afterwards ; for more modern 

 entomologists have discovered that singular production 

 to be derived from the egg of the inusca chamcekoti : see 

 Geoffroy, t. 17, f. 4. 



A full history of noxious insects hurtful in the field, 

 garden, and house, suggesting all the known and likely 

 means of destroying them, would be allowed by the 

 public to be a most useful and important work. What 

 knowledge there is of this sort lies scattered, and wants 

 to be collected ; great improvements would soon follow of 

 course. A knowledge of the properties, oeconomy, pro- 

 pagation, and in short of the life and conversation of 

 these animals, is a necessary step to lead us to some 

 aiiethod of preventing their depredations. 



