( v ) 



the potato disease. On examination by Prof. Westwood, this supposed 

 cause was found to consist in the attacks of Polydesmus complanatus, L. 

 After Guerin-Meneville's and Curtis's publications on the numerous insects, 

 myriapods, &c, which are found living in the diseased potatoes, he was 

 surprised that the now well-known potato disease should be attributed to 

 these attacks. 



The Rev. A. E. Eaton exhibited a patent revolving object-holder, used 

 by mineralogists, affording very great facilities in adjusting the position 

 of insects subjected to microscopical examination, thus allowing of the 

 examination of every part without removing the specimen. In the place 

 of forceps or fixed cork for the attachment of objects, this holder has 

 at the extremity of the arm a perforated cylinder that is made to rotate 

 by means of a chain movement connected with a milled wheel at the 

 opposite end of the arm. To adapt them for entomological work the holders 

 on sale require a hinge or cradle-joint to be made in the stem just above 

 the swivel, to work in the direction of the length of the arm : this is 

 preferable to a ball and socket-joint. The perforation in the cylinder wa8 

 filled with cork to receive the specimen pin. 



Sir Sidney Saunders stated that his attention had been called to a 

 typographical error, which had escaped notice in the recently-published 

 part of our ' Transactions' for 1883, by the omission of the word " tarsis" 

 (p. 9, line 7), although obviously implied by the context in the definition 

 " 5-articulatis." Some further details of the fore tibiae, as exhibited in 

 PI. II., fig. 23, should likewise have been inserted here, by the addition of 

 " apice latis, utrinque in dentes validos, latere externa tres latere interna duos, 

 productis." 



Sir Sidney Saunders also proposed to characterise the vegetable-feediug 

 fig-insects as follows : — 



" Sycophagides. — Larva intra ficum e germinibus educata. Mares 

 apteii, ut adhuc coguiti. Fceminee alatse, capite fossula longitudinali 

 dorsali, antennis prope fossulse introitum insertis, intra quam retrorsum 

 vertentibus incolumes servantur, articulis ultimis 3, 4, vel 5, clavam plus 

 miuusve laxam formantibus ; abdomine longiore quam lato ; terebra rlexili, 

 exserta, arcuata. 



" Divisio 1. Pkionostomata. — Mares mandibulis parvis ; abdominis 

 segmeutis basalibus inflatis, reliquis tenuibus, retiactilibus, saepe subtus 

 recurvis (rarius supra dorsum reflexis — Sycocrypta, Coq.). Fceminm man- 

 dibulis appendice exarticulata, latere interno serrata, ad basin affixa ; 

 antennis articulo 3tio vel 4to in spinam validam acutam externe producto, 

 articulum sequeutem oblique prope basin accipiente. 



" Divisio 2. Haplostomata. — Mares, a paucis speciebus chaiacteres 

 desumpti, elongati, angusti, depressi, mandibulis maximis, abdominis 

 lateribus rectis, segmentis laxis, extimo late truncato, plerumque ut videtur 



