APIS. 



[ 65 ] 



APUS. 



A 'PIS, L. — A genus of Hymenopterous 

 Insects. 



A. meUifica, the honey-bee, pi'esents some 

 interesting- points of structure. 



The proboscis (PI. 3.3. fig. 2o) agrees 

 essentially with that of Anthophora. The 

 " tongue " (labium*) is a very beautiful and 

 favourite microscopic object ; its minute 

 structure requires a higher power than that 

 used in maldng our sketch, to render distinct 

 the elegant transverse ridges or folds and 

 the terminal liairy lobe. 



The legs are peculiarly formed for the 

 special purpose of collecting and carrying 

 the poUen of flowers. The tibife of" the 

 hind legs are dilated, smooth on the outside 

 in the neuter or working bees, and hollowed 

 into a shining plate (PI. 34. fig. 46), whilst 

 the basal joint of the tarsi is hooked at its 

 outer superior angle and dilated into an ob- 

 long or somewhat triangular plate (PL 34. 

 fig. 4a), which is furnished with transverse 

 rows of hau's, forming pollen-brushes. 



BiBL. Westwood, Intr. &c. : Cm-tis, Brit. 

 Ent. 769. 



APLAXATISM. — Freedom from spheri- 

 cal aberration (in lenses). 



APLIDIUM, Sav.— AgenusofMollusca, 

 of the order Tunicata, and family Botrjd- 

 lidae. 



The common mass is from 1 to 3 inches 

 high ; and the animal bodies about J-| inch 

 long. Four British species : — 



A. Jicus, dark olive, orifices six-rayed ; 

 A. fallax, honey-yellow, with white' and 

 brown specks, orifices circular ; A. 7mtans, 

 straw-yellow, tinted with brown, orifices 

 invisible; and A. ven-ucosum, olive-green, 

 orifices entire. 



BiBL. Forbes and Hanley, Brit. MoUuxca, 

 i. 10. 



APOTHECIUM.— The name applied to 



Fig. 26. 



Dirina Ceratoniae. 



the female or spore-fruits of the Lichens, 

 ^everal special names have been applied to 



the apothecia, namely, pelta, scuteUa, patella, 

 scyphus, nrhiculus, lircUtt, and verruca, indi- 

 cating the forms occurring in particular 



Fig. 27. 



Fi£r. 28. 



Fig. 27. Apothecia, magnified. Fig. 2S. Thecoe and 

 paraphyses, from a vertical section of an apotliecium, 

 magnified 200 diameters. 



genera. They are shield-shaped, flat, cup- 

 shaped, globular, papilliform bodies, or linear 

 ridges, upon the upper surface of the thallus, 

 either immersed, superficial, or elevated on 

 peduncles. They contain the thecse or spore- 

 cases. For the structure, see Lichens. 



APPENDICULARIA, Cham.— A genus 

 of Mollusca, of the order Tunicata, and 

 family Salpidae. 



1 British species; A.JlagelUna. 



BiBL. Gosse, Mar. Zoot. i. p. 37; Cha- 

 misso. Nova Acta Acad. Cur. x. ; Huxley, 

 Phil. Trans. 18-51, p. 59,5. 



APTOG'ONUM, Ralfs.-A genus of Des- 

 midiacere. 



Char. Filament elongated, triangular or 

 flattened ; joints bicrenate at the free mar- 

 gins ; an oval foramen between the joints. 



Kiitzing and others placed this organism 

 in the genus Desmidiian, where it might 

 very well have remained. 



A. Desmidimn. Joints in front view 

 quadrangular, broader than long. 



a. Filaments triangular, regularly twisted, 

 crenatnres rounded ; length of joints 1-1-500", 

 breadth 1-1000" (PI. 14. fig. -5-5, front view ; 

 fig. 52, side view). 



/3. Filaments flattened ; crenatnres shal- 

 lower and slightly angular. 



A. Baileyi. P'ilaments not cronate ; 

 joints about equal in length and breadth. 

 American. 



The latter cannot- be retained in this 

 genus, unless the characters bo altered, on 

 account of the absence of the crenatnres 



BiBL. Kalfs, Br. Besmid. pp. 03, 208. 



A'PUS, Scop. — A genus of Entomos- 

 traca, of the order Phyllopoda, and family 

 Aspidephora. 



