7i)2 MR. C. 1'. ItOL'SSKLKT (»N [M:iy'24, 



KXI'LANATION UF VLXTK LXXIV. 



Kig. 1. l',>sti'i-i()r view of tl»e right tympanic inembranu of Balaiiopfrro mnscnlus 

 LiiniiiHis, showing its attachment to tlio malluns. 



'(. Head of malleus with tlic two articuhir surfaces for the incus. 



/'. Manubrium of maHens. 



c. Processus h)ngus of maUeus. 



'/. Portion of the li]) of tlie tympanic l>one to which the processus longus 



of the nniUeus is fused. 

 e. Ligament of tympanic membrane. 

 _/". Sac-like tympanic membrane. 



.</. Portion of the mucous membrane lining the tympanic cavity. 

 /(. Wall of external auditory canal which lias been cut near its junction 



with the rim of the tympanic membranusac. 



Kijr '2. riuii' of I'ar-wax from the external auditory meatus of linlfenoplern mitsriilus 

 Linna'us. A. Dorsal view of plug. 15. Posterior view. 



II. Cup-like portion for the recejjtion of tlie tympanic membrane. 

 1). Flattened distal i)ortion. 



Fiir. ;?. X'entral view of the left tymjjanic boue and inner portion of tiie cMtermil 

 Muilitory meatus oi Baltenojitcra miisciilii.i l.inn;ens. 



(I. Inner portion of external auditory nu'atus with the ventral wall 



removed to show the tympanic mem Inane and ping. 

 h. Plug of ear-wax. 



c. Tvmpanic membrane. 



d. Tympanic bone. 



2. Zoolooieal Results of the Third Tiin^aiiyikii Ex])e:]iti()n, 

 conducted by Dr. W. A. Cunuington, F.Z.»S., liK)-l- 

 1005. — Re]ioi-t on tlic Rotifera. By Charles F. Rous-; 

 SKI.FT, F.K.M.S.* 



[Received April 7, 1910.] 



(Plate LXXV.t) 



Amongst the collections In-onght back by Dr. W. A. Ciuinington 

 from the gi-eat inland lakes of Central Africa, visited dining this 

 Expedition, were a number of tubes containing fine surface 

 I'laukton nettings which I have searched over for Rotifera. 



The gatherings were not specially ntade with a view to collect 

 the.se creatures, and being, mort'over, made only from a boat in 

 the open water and never among the vegetation near the .shore, 

 these circunistances may account for the comp.iratively poor 

 results ohtaiued. 



The ( 'ollection is, however, interesting and important from the 

 fact that, with the e.xception of H species (exdud'iig doul)tful 

 one.s) collected in and near the Victoria Nvanza 1)V Dr. Stiddmann 

 in 1H!I1 and described l)y Dr. Ant. ColUn (1) in 189(5. and 14 

 additional species (again excluding the doubtfid ones) collected in 

 the Vi(!toria Nyanza by Dr. Horgert in li)U4, and descril)ed by 

 l*n»f. E. von Daday (2) in 1907, no previous records of Rotifera 



• Comumnicated by Dr. W. A. ("i;.\nisoton, F.Z.S. 

 t For ex))lanation of the Plate see p. 7'.t!). 



