INTRODUCTION. 



Notodonta. 



Pygcera. 

 IT. 

 Endromls. 



Aglia. 

 Satumia. 

 Lasiocampa. III. Eutricha, 

 Cnethocampa 

 Eriogaster. 



Cossus. 



Hepialus. 

 I. 



Zeuzera : Oihticos. 



Psyche. 

 Limacodes. Nudaria. 



IV. Penthoptera. 

 : Dasychira. Arctia. 



Hvpercampa. 



••••■> 



Callimorpha. 



Upon an inspection of the above tables, it will be manifest that 

 the principal difference between the two methods exists in the con- 

 terminous genera alone; though it must be added that Dr. Hors- 

 field has not entered into details as to the succession of his groups, 

 or their affinities to each other; neither does the first table exhibit 

 the five groups in accordance with the schemes employed by Mr. 

 MacLeay ; my object being simply to show that the difference in 

 our arrangements is in reality more apparent than real, and seems 

 to depend upon the relative position of the lines of separation, as 

 indicated by the dots ; — a fact which is again observable at that 

 point of the fourth circle which impinges upon the Lithosiidae, and 

 consequently renders the position of the genus Hypercampa de- 

 bateable. 



The number of genera herein given will doubtless alarm many 

 persons : it however seems to me, that the extensive and multifa- 

 rious nature of the subject demands the adoption of such as I have 

 indicated in the following pages *, without being shackled by nu- 

 merical convenience. Upon this point there will probably always 

 exist considerable diversity of opinion ; but it is allowed by all {xir- 

 ties, that some addition should be made to the genera instituted, 

 as adopted by Linnaeus, though the followers of that great man rest 

 contented by admitting a few new genera only, and totally disre- 

 gard every attempt to increase the number ; stating as reasons, that 

 they merely tend to burthen thfe memory unnecessarily, and to 

 introduce confusion into the science. Another reason assigned by 

 them for not introducing new genera into their systems, is, that 

 many of them contain one species only ; not considering the very 

 confined knowledge we have of the latter, and the vast accessions 



* With regard to the number of genera, it has been well observed by 

 Mr. MacLeay, that writers are frequently guided in tbeir views by the ex- 

 tent of their collections ; persons with small collections not seeing that 

 necessity for subdivision which those with larger ones think expedient. 

 It may be added, that a writer, who most strenuously opposes the forma- 

 tion of new genera, has adopted, without restriction, all the genera which 

 I have proposed in my " Illustrations," to the Spharidiidae, and which are 

 correspondent witli those in the following pages ; and that other writers 

 who have succeeded me in the Haustellata have subdivided some of the 

 genera therein given. 



