224 Mr. F. W. E.lwanls on 



justified ill allocatiuoj it to Chironomns, hut iu its larv il and 

 ni4)al Staines the species shows a much gre iter relationship 

 to Tanijtarsas. The early stages of C. clavaticras have, 

 iudeel, baeu described iu detail by IJiuse (Ardiiv fiir 

 Hydrobiol., Suppl. B;l. ii. p. 73, 1913) * as tliose of a 

 Tain/ tars us, which, ou the authority of Thieueuiaun, he calls 

 " Tanytar.-ms flexilh, Liuue," thouj^h he states that the 

 lirvae have uot yet beeu reared. Why Thieueuiaun adopts 

 tliis uauie, which has usually beefi allotted to a totally 

 differeut species of Chirouomus, is far froiu clear; but, siuce 

 Bause states that Thieuemauu himself iuteuds to give 

 reasons for the identification in a later publication, I refrain 

 from comment at present. 



To the accounts given by Reaumur, Lauterborn, and 

 Bause of the early stages of this species I can add the 

 following points: — The egg-mass is about 6 mm. in length, 

 1 mm. broad, pointed at each end ; those I observed adhered 

 by one end to water-weeds, but whether this was accidental 

 or whether they were fixed in this position by the Hy I could 

 not determine. The eggs in the egg-mass are arranged in 

 a rather indefinite spiral ; counts of the number in two 

 separate masses showed 182 and 163 respectively. The 

 larvie emerge from the egg through a longitudinal fissure, 

 and when newly hatched are about 00 mm. long and practi- 

 cally colourless, tlieie being only small patches of yellowish- 

 green granules at the sides of abdominal segments 2-7 and 

 along the sides of the intestine ; they have no trace of 

 ventral blood-gills or of the hump on the eighth abdominal 

 segment ; " Lauterborn's organs" are present at the apices 

 of the second and third anteunal joints, as in the full-grown 

 larva. The second stage larva much resembles the first f, 

 but is a little over 1 mm. long, and has a slight hump on 

 the eightli abdouiinal segment and a slight red tinge behind 

 the head and in the middle of the body. In the third stage 

 the red colour of the body i;. more widely spiead, but not 

 strong; the hump on the eighth abdominal s( guicnt is well 

 <ievelop( d. and blood-gills are present on the seventh segment, 

 but are as \et colour, ess and have not their full length. The 



* Tlie earlv stages of C. clavaticrus npparently agree in every respect 

 with Brtuse'sdescriptiou aud tigures of T.fte.filis, but there is, ufci-iujie, 

 a possibility tliat there may be two ch).sely allied .spt-cies. 



+ Miall and IlaniuiMiid state (' IJarlequin-lly,' p. 176) that the pecu- 

 liarities of the newly-hatched Lirvadi-appear alter thejird moult: It is 

 just possible that what I regarded as secund-stage larvae are merely lirst- 

 staye individuals which have grown in size. 



