A FLAT BEETLE. 



187 



regret the necessity for selecting only one species as an example 

 of them. 



The members of the genus Helaeus are found throughout 

 Australia, and, while agreeing in general form, have some remark- 

 able varieties of detail. Among the details in which they agree 

 is the flattening of the sides of the thorax and elytra, the abdo- 

 men and radial thorax being rounded, as is shown in the illus- 

 tration. As to the head, it is quite invisible when the insect is 

 viewed from above, being completely hidden under the flattened 

 perthorax. There are no wings. 



The colour of the present species is rather dark reddish brown, 

 very much like that of the " jumbles," to which reference has 

 been made in the description of the Mormolyce, or Fiddler Beetle, 



Fig. S9. — Helseus perforatus. 

 (Reddish brown.) 



on page 40. As is the case with that Beetle, the colour is darker 

 in the middle of the thorax and abdomen. The sides of the 

 elytra are very much flattened and slightly turned upwards, so 

 as to give to the insect the form of a shallow dish. We have 

 no British insect which is exactly like it in this respect, but the 

 flattened body of the common Water Scorpion {Nepa cinerea) 

 will convey a tolerable idea of the Helseus. In spite of the 

 large size of the elytra, there is not more material in them than 

 would be the case were they not flattened, but they are so 

 squeezed out that they are scarcely thicker than the paper on 

 which this account is printed. 



At the first glance at the insect it is evident that the middle 

 of the elytra is covered with a dense coating of long hairs that 

 stand boldly upwards, but have a very slight curvature at the 



