OF CADDIS-FLIES DESCRIBED BY LINNiEUS. 



731 



tioD, to conviuce us that tbe author did not iutend tlie Sialis, which 

 lie, moreover, probably describes as Hemerohius latarius at p. 384 

 (No. 1513). His words, " Sedet alis deflexis uti Phalaena," clearly 

 indicate the family to which it belongs. If used in comparison 

 with all the foregoing species, they have special weight, for of the 

 next following (P. hicandata) is said " alae iucumbentes, non de- 

 flexis." The same may be said of the words " cauda simplex absque 

 stylis prominulis," whereas the following species is indicated by 

 "cauda duabus setis autenniformibus." It is therefore a true 

 " JBliryganea " and not a Ferla. Its wings are described as " re- 

 ticulata) ; venis fuscis maxime reticulatis, praesertim ad margine 

 extcriorem." The colour of the wings has thus some resemblance 

 to that of Ph. reticulata, Jj. ; and the insect can be sought for neither 

 amongst the LimnopliilidcB nor the Leptoceridce, for there is no 

 species in these families with such a colour. Only the Hydro- 

 psychidce and RhyacopMlidce remain, and it is possible that in one 

 of these the species may be found. The families have the " margo 

 exterior " (inner margin) " admodum dilatatus " in comparison 

 with the others, and some of them by day are more tranquil than 

 is usual, thus justifying the use of the words " ubi sedet tranquilla." 

 The v^'ords os duobus denticulis et quatuor a palpis " point to a 

 Hydropsyclie and not to a Bhyacopliila, which the strong fuscouB 

 reticulation also makes clear. The denticulation of the mouth 

 and palpi is such that it may not have escaped the notice of such 

 an acute observer as Linnaeus. His words probably refer to the 

 maxillary processes and the processes of the labial palpi ; but 

 the words " antennae corpore dimidio breviores " seem to nullify 

 this supposition. The antennas in Hydropsychea.ve seldom longer 

 than the wings, but they are always more than half the length of 

 the body. They may have been broken in Linnaeus's type, as 

 they were in that of his Ph. phalcenoides, of which he equally says, 

 " antenna? corpore dimidio breviores." I am therefore convinced 

 that he did intend a Hydropsyche ; and among the Swedish species 

 only H. instahilis auct. could be intended, for the description 

 agrees tolerably well with it. The wings are cinereous, their 

 fuscous reticulation is especially strong toward the inner margin, 

 and the thorax is yellowish at the sides. 



PnuraA^^EA bicatidata (No. 1489) is a Perla, as is well known. 



Pn. NIGRA (No. 1490) is Mystacides atra, Pict., as I have already 

 hown in the Ofversigt af K. Yet.-Ak. Forhandl. 1870, p. 151. 



