PLOTERES. 539 



oval, and surmounted b}' seven elongated filaments, which 

 serve, while the egg is in the oviduct, to form a kind of cup 

 for the reception of the succeeding egg, but which are recurved 

 when the egg is discharged." (Westwood.) 



Galgulid^ (Galgudini) Burmeister. This small group con- 

 sists of a few species which have the hind legs formed for 

 running. The body is short, broad, flattened, and the head is 

 broad with pedunculated eyes, and the four-jointed antennae 

 are concealed beneath the ej-es, while the ocelli are present. 

 These insects are said to live on the edge of the water, "bury- 

 ing themselves in the sand, especially in the larva state." 

 The group is interesting as forming a connecting link between 

 the aquatic and terrestrial plant-eating species. 



In Galgulus the third antennal joint is small, the fourth 

 minute and rounded. G. oculatiis Fabr. is uniformly brown, 

 the upper surface granulated, and beneath blackish. 



Ploteres Latreille. These insects are long, narrowing 

 alike towards both ends, being shaped like a wheny, and with 

 their long legs they course over the surface of ponds and 

 streams, moving backwards and forwards with great facility. 

 The}^ are among the earliest spring insects. The body beneath 

 is furnished with a coating of plush, to repel the water. The 

 four-jointed antennae are long and slen- 

 der, and the fore legs are partial^ rap- 

 torial for seizing their prey. Wingless 

 insects (evidently mature as they are 

 found coupling) occur in this family, as 

 among the Cimiciclce. Thus, there 

 are apterous forms in the genera Gerris, 

 Hydrometra and Velia, while in Pyrrlio- 

 coris apteras and Prostemma guttula 

 there are individuals partially winged, 

 "which no one regards otherwise than as specifically identical 

 with the full-winged specimens of the same species, . . . but 

 must be compelled to regard them as imagines with peculiar 

 characters of their own, someAvhat analogous to the neuters, 

 or undeveloped females or the bee ; but yet more perfect than 



