274 THE SUGAR BEET. 



the second division of Rypophagous pentamera'). The 

 species that attack the hectare: 1st, Silplia opaca f' 

 2d, Silpha thoracia.^ 



We cannot understand why insects of this variety 

 should, ever trouble the sugar beet, as their habits and 

 tastes are unlike any other similar enemy of the root. 

 They have a most fetid odor, which is sufficiently strong 

 to be transmitted to all the neighborhood. The cause 

 of this we imagine to be the food they prefer, which is 

 dead bodies in an advanced state of decomposition. 

 They are distinguishable by the flattened form of their 

 bodies. 



The larvse when deposited by the female are in a 

 very advanced state. 



Silpha opaca. — This insect made its "debut" in 

 Sweden and was noticed in France ten years ago. 

 The destruction it causes takes place during the early 

 portion of the spring, and lasts but a short time. It is 

 well to plant (if not too late) the seeds which will 

 come up after the metamorphosis has commenced. 



Silpha thoracia (see fig. 69), — Its color is black, with 

 a yellow border. 



Altica* or Haltica. There are a great variety of 



' The above is West wood's classification. The German classification is the 

 twelfth family (Silphidae). 



' Silpha opaca. See for further information Guerin, Ann. Fr., 1846, Bull, 

 p. 72. 



' Silpha thoracia. See for further information Linn6's Sys. Nat. (2), p. 

 57.1. Eschsch, Deg. Cat., 3d, p. 132. 



* The word Altica is taken from the Greek, which signifies to jump. 



