Contrlbution towards the history of a new form of 

 larvae of Psychodidae (DIptera), from Brazir). 



Mit Tafel LXXVIII und LXXIX. 



The perusal of Baron Osten Sacken's "Contributions to the Study of Lipo- 

 neuridee" (Berl. Ent. Zeitschr., vol. xl. 1895, p. 148), a copy of which I owe to the 

 kindness of the author, recalled to my memory a group of minute Diptera, the 

 larvae of which abound around the waterfalls in our woods, in the neighbourhood 

 of the larvae of Curupira {Blepharoceridcv), and are remarkable for being pro- 

 vided, like the latter, with a longitudinal row of suctorial ventral discs. 



While the larvae of Curupira are fastened to the bare rocks, over which 

 the stream of water falls down perpendicularly, those of the Maruis {Marui is a 

 diminutive of Marü, fly, in the Tnpi-\a,ngua.ge, adopted in Portuguese) live on 

 rocky walls, covered with a slippery carpet of algae, and kept moist by the spray 

 of the waterfaUs or by the drops of water running down from above. I dis- 

 covered them in 1881 in looking for a small Helicopsyche that occurs in similar 

 localities, and began to make a special study of them, but was prevented by 

 circumstances from continuing it. The Information I had obtained about them 

 seemed to me too fragmentary for immediate publication. As I cannot, at present, 

 expect to complete these observations, although I had hoped it at that time, I 

 feel inclined to publish now at least some of my old drawings, and to accompany 

 them with some remarks for the sole purpose of calling the attention of future 

 visitors to our country to these remarkable animals. 



For this particular purpose I shall begin by describing my very simple 

 method of catching them. The larvae are so small that they are hardly recog- 

 nisable in situ, and, therefore, can hardl}- be taken hold of singly. The flat of 

 the hand is, therefore, passed over the slippery wall, the surface of the hand is 

 scraped with a knife, which is then rinsed in a tumbler of fresh water ; the larvae 

 thus obtained are soon found fastened to the sides of the tumbler, the muddy 

 water of which is then replaced by fresh. Unlike the Curupira-laxvse, which 

 die very soon, those of Maruina bear confinement very well, change into pupae, 

 and the majority of the latter produce flies in a week or two. Whether the mould 

 which appears on pupae very soon after they are dead, is the cause of the death 

 or its consequence, I cannot say. 



i) Trans. Ent. Soc. London 1895. p. 479—482. 



