242 [April, 



with numerous points. On segments 3 — 5, anteriorly on either side, 

 are two, on 6 — 7 three, little hooks ; on the posterior margin of seg- 

 ment 5 are six or seven such hooks. The dorsal respiratory filaments 

 are on segments 2 — 4, the ventral on segments 2 — 6; lateral line 

 conspicuous from segments 6—8, and with long grey hairs. Anal 

 processes long, slender, stout at the base, curved outward at the apex. 



The case (see figures) is a conical sand-tube, strongly attenuate 

 posteriorly and much curved. The head end is somewhat produced 

 above, so as to protect the head of the larva ; the anterior opening is 

 therefore very oblique. The surface of the case is very rough, and 

 larger sand grains are arranged on the sides. The cases of the pupae 

 have the anterior end closed with very fine sand grains, and are mostly 

 attached to the under-side of large stones, often mixed gregariously 

 with those of Silo nigricornis. They adhere closely to the stones. 



There is another matter of importance concerning the preparatory 

 conditions of Apatania muliebris. It is stated in Mr. McLachlan' s 

 " Revision," p. 216, and (Suppl.) p. xlvi, that there is strong evidence 

 to induce us to believe that this species propagates parthenogenetically. 

 In order to prove this incontestably we must breed the insects from 

 eggs laid parthenogenetically. There is, however, stronger evidence. 

 Mr. McLachlan could never find a <$ of this species. And still 

 stronger is the fact that we find no £ pupae. During the several years 

 tbat I have had this insect under observation, I have never seen a $ 

 pupa amongst the large number examined. The spring where the 

 species occurs is very small, and I know all the Trichoptera inhabiting 

 it. The others are Drusus trifidus, McL., Halesus auricollis, P. (un- 

 usually small), Silo nigricornis, P., Crunoecia irrorata, Curt., Bercea 

 pullata, Curt., and Plectrocnemia conspersa, Curt. ; mostly very 

 abundant. 



Kl. Weinberge, 24, Puchmajer-gasse, Prague : 

 March 1st, 1889. 



[This is a valuable communication from several points of view. 

 It practically establishes as a fact that Apatania muliebris propagates 

 parthenogenetically (and A. arctica of Spitzbergen, and Nowaja Zem- 

 lja, &c, is about in a parallel condition), yet one hopes, in such 

 cases, that a male may occasionally exist. It also proves that there is no 

 great dissimilarity of habits between Apatania and allies and the rest 

 of the Limnophilidw. Nevertheless, there is a good deal of discre- 

 pancy in the structure of the perfect insects, and Wallengren recently 

 formed a distinct Family for th*"^ reception (Apataniidce). — E. 

 McLachlan]. 



