EEEATA AND ADDENDA. 



7 line 5 for " pterpoda" read " i)teropocla." 

 — "13 for " bracMapoda" read " braeMopoda." 

 11 " 16 for " pector" read " pecten." 



15 " 30 for "Mr. Robert" read "Mr. George Roberts ;" the 

 statement is undoubtedly correct. 



22 " 16 for " slerotic" read " sclerotic." 



23 Note. Striped muscularfibrehas been observed in ^rt/prj!. (Huxley.) 

 28 line 8 erase the words " wben withdrawn." 



28 rig. 16 a, anterior; ]), posterior; /, lateral; r, rachidian. 



30 line 27 erase " and by four in the brachiopoda." 



39 " 22 the " tubular structiu-e" oijnmia is probably occasioned by 

 the growth of a confervoid sponge between the laminBC. 

 (Quekett.) 



46 " 13 erase the Avord "cylindrella." 



50 " 7 for " brachiopoda" read " opistho-branches." 



52 erase lines 20—23, and see p. 245. 



54 line 12 see Supplement. 



65 M. Verany and 11. MiUler have shown that the Eectocotyle is 

 developed in place of the right arm of the third pair of the 

 male cephalopod, and spontajieoiisJy detached. See Supple- 

 ment. 



67 line 8 from bottom, /or " dorsal" read " ventral." 



68 Tremoctopiis is a sub-genus of Octopus, not of Philonexis. 



70 line 16 add " Type, Loligo Aalensis, Schubler." 



71 " 14 for " Fidenas ? Gray" read '• R. palpebrosa." 



79 Note, for " the apocryphal genus spongarium was founded on" 



read " most of the so-called spongaria are." 

 89 Sub-genus 6, Diploceras (Salter). The shell is supposed to have 

 resembled Gonioceras, and the external tube to be a simple 

 cavity forifled by the approximation of the lateral angles. 

 94 line 15 (and PI. III. fig. 4,) for " Rhothomagensis" read "Rotho- 

 magensis, from Rothomagum, Rouen." 

 100 " 6 for " riam" read " rima." 



105 " 8 for " Strombidia, Sw." read " Rimella, Ag." 



106 erase line 3. 



108 Admete (viridula) is a boreal form of Cancellaria, without plaits. 



