22 E. T. Atkinson — Notes on Indian Rhynchota. [No. 1, 



of copper wire : the whole 320 gi'ains being, of course, equivalent to 

 1"032, or thirty- two thousandths— a figure far above any degree of salt- 

 ness of sea water, but chosen on account of its convenience of divisa- 

 bility : — thus, the 320 grains of wire doubled, straightened out and cut, 

 gives '016, or sixteen one-thousandths : of which make sixteen coils, or 

 loops to denote it, of one piece. The other piece doubled as before and 

 cut gives '008, and so on, until the one-sixteenth of a thousandth is 

 arrived at, — a fraction which will be found to readily sink the bottle, or 

 * turn the scale ' of this frictionless balance. 



Below is added a diagram (PI. IX) for corrections for temperature 

 of fresh water ; and a suitable table of corrections for temperature of sea 

 water will be found in ' Maury's Physical Geography of the Sea,' and in 

 many other books of a like character, for those who like to seek out for 

 themselves the " exqinsite and beautiful compensations " which as a part 

 of its machinery the sea salts provide in the physical economy of the 

 Ocean. 



III. — Notes on Indian Rhynchota : Heteropteea, No. 1. 

 By E. T. Atkinson, B. A., President. 



[Received and Read December 1, 1886.] 



Order Rhynchota, Burmeister. 



Hemiptera, Linn. : Rhyngota Fabr. : Prohoscidea, Scop. : Dermaptera, Retz. 



Insects with an incomplete metamorphosis, not exhibiting the mark- 

 ed changes from larva to pupa and imago observable in the Lepidoptera : 

 furnished with a mouth or rostrum which is fitted for piercing and 

 sucking. The rostrum is usually 3 — 4-jointed and contains four seta that 

 arise from the anterior portion of the lower surface of the head and 

 represent the maxillae and mandibles of other orders of insects. An- 

 tennae with 3 — 5 joints, rarely more ; the wings are usually four in 

 number, but are sometimes abbreviated or altogether wanting. 



Suborder Hemiptera, Latreille. 



The first pair of wings (hemelytra) are horizontal, with the veins 

 arranged differently from those of the second pair (wings), and usually 

 comprise a basal coriaceous portion {corium and clavus), and a mem- 

 branous portion (membrane) at the apex. This membrane is sometimes 

 entirely absent. The wings are entirely membranous and are sometimes 

 absent. 



