74 B. GRASSI AND A. SANDIAS. 



sets in, there is in my belief a precocious maturation of the 

 generative organs (neoteinia). This interpretation is sup- 

 ported by the fact that they become mature here in Sicily at a 

 time when the summer heat is well marked, and before the 

 ground has become unduly dry. 



Catania; December, 1888. 



[The transformations of the Embiidse are practically un- 

 known, and the few facts recorded have simply increased the 

 confusion which has surrounded it. While reserving the details 

 of the metamorphoses of Embia urichi, it is sufficient to say 

 here that the females of Embiidse are practically ametabolous, 

 the only essential morphological change during growth consist- 

 ing in an increase in the number of antennal joints. The male 

 of Professor Grassi's species undergoes the changes in the form 

 of the mandibles and the posterior extremity which supervene 

 upon the last ecdysis. In addition, the males of the winged 

 species, such as Embia urichi, are normally hemimetabolic, 

 and pass through a nymph stage, as in other Orthoptera 

 (s. lat.) The form described by Mr. McLachlan^ as a nymph has 

 been conjectured by Hagen to be a micropterous form. This is 

 quite erroneous. The chitinous coverings thrown off at the 

 ecdyses are extraordinarily thin and transparent, and quite 

 pigmentless, except over the tergal and sternal plates. In the 

 nymph of E. urichi the pterothecse are so extremely delicate 

 as to be indistinguishable without very careful examination, and 

 the young wings which they enclose appear quite distinct and 

 separate as in the imago, but of very small size. But if speci- 

 mens preserved in alcohol, which causes the body to shrink 

 away from the integuments, are examined, or if the nymph- 

 skin is removed intact by a longitudinal incision, like the 

 ecdysial fissure, the existence of the pterothecal coverings to 

 the small wings becomes evident. The structure of the thoracic 

 segments and the mode of attachment of the legs is alike in 

 both winged and wingless forms, and is typical of apterous 

 * • Journ. Linn. Soc.,' xiii (1877), pp. 383-1, pi. xxi. 



