— 2 — 



There are altogether 21 species enumerateci as determined (1), of which 

 7 are described as new. There are also a number of nymphs of various 

 species of Gerridae, but I feel that at present my knowledge is not 

 suflìcient to discriminate them ali clearly. The types of the new species 

 are ali in the collections of the Museum, and duplicates of most of the 

 species enumerated are in the collections of Dr. Montandoli & myself. 



(1) Hydromelra argentina Berg, bas been recorded by Montandoli (1895. 

 Pulì. Mus. Torino, voi. X, n. 219, p. 8) as baving formed part of Dr. Borelli's 

 captures in the Argentine (Resistencia) but it was not included in the insects 

 1 bave examined. 



&iò - Tip. Pietro Gerbone - Torino. 



