GENUS CALANDRA< 105 



'One essential point in all storehouses for grain is, undoubtedly, frequent whitewashing 

 and thorough ventilation, as there appears to be much testimony corroborative of this great 

 preventive to the ravages of this minute destroyer. 



' A correspondent of the London Mark-lane Express, in speaking of the corn weevil 

 says : " Some years ago, we found a house overrun with weevils : after numberless at- 

 tempts to destroy them, we were led to observe that they were almost entirely on the south 

 wall (our rainy side), and that they appeared to breed in incredible numbers in an un- 

 usually damp spot or corner. Taking the hint, we cased the wall on the outside with slate, 

 and made the house in every respect perfectly dry, and in a short time the weevils died 

 off and disappeared. Since adopting this precaution, we have not the least trouble, and 

 have only been reminded that such an insect exists when an accidental spot of damp has 

 appeared to generate them again. We think ourselves, therefore, entitled to say, that these 

 Insects require moisture ; and that if the grain and granary, as both ought always to be, 

 are dry and healthy, weevils will not long remain. This plan bears the merit of costing 

 less than nothing, because the injury that wheat sustains directly from damp is more than 

 equivalent to the expense of keeping premises dry, leaving its indirect influence in the 

 generation of weevils out of the question." ' 



SlLVANUS SURINAMENS18. ( Plate 11, fig. 3.) 



The following is Mr. Gavit's account of this insect : 



' The insect accompanying the Calandra, and usually found in granaries in this country, 

 is named Silvanus surinamensis, the com silvanus. This insect was named by Linn.eus, 

 being sent to him from Surinam by one of his pupils. Fabricius, from its infesting stores 

 and warehouses, called it ^nobium frumentarium, and subsequently Derwies^es sexdentatum, 

 from the spines on the side of the thorax. LiNN.a;us's name, however, has the right of 

 priority. 



« S. surinamcnsis is only one line and a quarter long, and very narrow : it is flat, of a 

 rusty brown color, thickly and coarsely punctured, and sparingly clothed with short de- 

 pressed yellow hairs. The head is large and subtrigonate : the nose appears truncated, 

 but it is semicircular in front, and conceals the mouth, which is composed of an upper 

 and under lip, and two little horny jaws, maxillae and palpi. The antennse stout, straight 

 and pubescent, nearly as long as the head and thorax, and eleven-jointed ; the basal joint 

 stoutish, tlie terminal ones forming an elongated club (fig./). The eyes are black, small, 

 and coarsely granulated. The thorax is perfectly oval, and a little wider than the head at 

 the middle. There are three ridges down the back, forming two broad channels, and on 

 each margin are six teeth. Scutellum minute ; the wing-covers long, elliptical, and broader 

 than the thorax, with four slightly elevated lines down each : between them are double 

 rows of punctures, and a series of little shining yellow bristles : beneath are two ample 



[Agricultueal Report — Vol. v.] 14 



