ii8 



NOTE ON THE LARVA OF OTTONIA CONIFERA. 



C. F. GEORGE, M.R.C.S., 



Kirton-in-L indsey. 



Mr. Evans, of Edinburgh, has succeeded in rearing the larvse 

 of Ottonia conijera from eggs laid by that mite. They are very 

 small and delicate, as well as active, and therefore rather 

 difficult to deal with. Mr. Soar has, however, succeeded in 

 making a fair drawing of the little creature. It will be seen to 

 differ very considerably from the other larvae figured in ' The 

 Naturalist ' for 1908, page 452. The most striking part is the 



n. — Larva of Ottonia conijera (dorsal surface). 

 h. — Larva of Ottonia conifcra (ventral surface), 

 i'. — Mouth opening of Ottonia conijera. 



Length 0'32 mm. Multiplied 170 times. 



formation of the mouth opening, which is circular in form, 

 and surrounded by a chitinous rim not unlike the toothed rim 

 of a watch cog wheel (see enlarged figure of this part). I 

 find a similar feature figured in a posthumous paper by the late 

 Professor A. C. Ondemans, of Arnhem (kindly sent to me by 

 Professor Van den Schruver) on ' Thrombi dium larven.', 

 plate v., fig. 14, \\hich he calls Allothromhidium tectocervix. 

 The next difference is that the shield of the cephalothorax is 

 striated longitudinally. Ondemans also finds this striation in 

 the larva of another creature as well as tectocervix, which he calls 

 ' Allothrombidiuin striaticeps ' (plate V., fig. 17), but in both 

 these creatures he figures the plate as divided into two portions, 

 whilst in conifcra it appears to be single, as shewn in the figure. 



Naturalist, 



