548 Microscopical Essays. 



A pellucid cryftalline animalculum, fu mimed with fmaller and 

 larger fplend.id globules fwimming about within it, the under-fide 

 convex, the upper-fide hollow, the fore-part forming a kind of 



up. 



121. Burfaria Hirundinella. Fig, 19, Plate XXV. 



Burfaria utrinque laciniata, extremitatibus produclis. 



Burfaria with two little projecting wings, one on each fide, the 

 fore and hind-part produced fo as to give them fome refemblance 

 to the head and tail of a bird. It is invifible to the naked eye, 

 but appears to be a pellucid hollow membrane under the micro- 

 fcope. They have no vifible interlines ; it moves fome what like 

 a fwallow ; a the head, b the tail, c one of the wings.. 



122. Burfaria Duplella.. Fig. 18, Plate XXV.. 



Burfaria elliptica, marginibus inflexis. Elliptic burfaria,. with 

 the edge bent in and out. 



A cryftalline membrane folded up, no vifible interlines, if we 

 except a little congeries of points under one of the folds. Was. 

 found among duck- weed. 



123. Burfaria Globina. * 



Burfaria fphaerica, medio pellucentiflima.. Spherical burfaria, 

 very pellucid in the middle. 



A fub- 



