JANUARY. 11 



The antennae are the two moveable appendages like horns, 

 which are so characteristic of insects; they are of various 

 forms, and assist greatly in determining the genera; it is 

 therefore necessary that the student should be acquainted 

 with the principal varieties they assume, and the names by 

 which they are distinguished. Some authors present a for- 

 midable list, but the most common are as follow : Setaceous, 

 when they gradually taper towards the extremity. Clavate, 

 when they grow thicker from the base. Filiform, when of 

 an equal thickness throughout. Moniliform, when composed 

 of a series of knots, resembling a string of beads. Capitate, 

 when they terminate in a knob. Fissile, when the knob is 

 divided longitudinally into laminae or plates. Per/Mate, 

 having the knob divided horizontally. Pectinate, having a 

 longitudinal series of processes like hairs, projecting from 

 them in the form of a comb. Plumose, when they resemble 

 a feather. Prismatic, when like a prism, or formed of three 

 sides. Fusiform, small at the two extremities, and thick in 

 the centre, like a spindle. Furcate, when the antennae are 

 divided into two branches like a fork. 



The number of joints in the antennas varies considerably. 

 Coleopterous insects have in general eleven joints ; the sting- 

 ing portion of the order Hymenoptera twelve or thirteen, 



