LIMNOPHILA. 201 



verticils (the antennas of L. tenuipes, % , are very long, filiform ; 

 compare the description of this species). The venation of this 

 group resembles that of L. quadrata 0. S. (Tab. II, fig. 9), 

 although the latter has only four posterior cells, and this resem- 

 blance may be indicative of a relationship. The same remark, 

 although in a lesser degree, may apply to the venation of the 

 genus Ulomorpha. 



Some general remarks on the venation of Limnophila may find 

 their place here : — 



1. The marginal cross-vein is apt to be very weakly marked in 

 many species of Limnophila; but I have never found it abso- 

 lutely wanting. I perceive it in two European specimens of 

 Idioptera, although Dr. Schiner mentions the absence of this 

 vein among the characters of the genus. 



2. Bhicnoptila (compare above, page 198) is the only Limno- 

 phila with an open discal cell, which I have seen, and this ex- 

 ceptional case is evidently due to the abnormal and abortive 

 condition of the whole wing. But it is worthy of notice that in 

 Bhicnoptila, as well as in those single specimens of Limnophila 

 in which the discal cell is adventitiously open, the anterior 

 branch of the fourth vein bears a double fork, similar to that of 

 Dolichopeza, the posterior branch having no fork at all. In the 

 Amalopina, when the discal cell is open, each of the branches 

 of the fourth vein has a fork (compare above, p. 191). 



3. The great cross-vein in the genus Limnophila is very often 

 nearer to the middle than to the inner end of the discal cell ; in the 

 subgenus Dactylolabis, however, it is usually near the inner end 

 of this cell. 



4. The venation is always somewhat variable in different speci- 

 mens of the same species, which applies especially to the relative 

 length of the petioles of the first submarginal and of the second 

 posterior cells ; also to the position of the great cross-vein, and 

 of the marginal cross-vein. These variations ought to be taken 

 into account in reading the descriptions of the species. 



Several larvae of Limnophila have been observed ; those of L. 

 punctata M. by Scheffer (in Rossi's System. Verz. Oesterr. Dipt. 

 p. 10), in decayed beech-wood ; L. (Epiphragma) picta by Bremi, 

 in oak-wood ; L. dispar M. by Perris (Ann. Soc. Entom. de Fr. 

 1849, p. 331, Tab. YII, fig. 5), in dry stems of Angelica sylves- 



