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The upper edge is called The flargin, to which 

 is often attached a uniform row of incurved spines, which 

 I call The Corona, there are also attached to the edge 

 of the harpe long spines which I term flarginal 

 Spines. The outer margin of the cucullus, where the 

 division usually occurs is called The Anal Angle 

 and is sometimes armed with a large Anal Spine. 

 Where the division is not evident, this position is some- 

 times occupied by a projecting column or thumb, which 

 I call The Pollex. The upper inner angle is some- 

 times produced to a point, and occasionally below this, 

 proceeding from the skin, on the inner side of the 

 cucullus, is another small papilla called The Digitus. 



The lower portion of the harpe I term The 

 SaCCUluS. This invests the base of the harpe, and is 

 free along the costal edge. It is attached to the outer 

 margin of the harpe, but is sometimes extended into a 

 free arm, almost to the extremity of the harpe. From 

 within the base of the costa of the sacculus, arises a 

 small organ which I have termed The ClavUS, 

 which may be rounded, produced, peaked or brush form. 



The central area of the harpe is occupied by a com- 

 plicated series of organs, which practically vary in every 

 species and afford a great help in differentiation. For 

 convenience sake they may be divided into The 

 Clasper and Ampulla. The Clasper which arises 

 toward the outer side and is generally a free arm, 

 produced from a peculiarly curved base, by which it may 

 frequently be recognised. Sometimes it is foot shaped, 

 as in the Noctiice, in which case the terms, toe, heel, &c., 

 indicate the parts spoken of; or it may be a simple 

 swelling, entirely, attached to the skin, when it is spoken 

 of as, not free. On the inner side of the central area is 

 The Ampulla, a process arising direct from the skin. 

 It is a very variable organ and difficult to locate. It is 

 often a small papilla, sometimes only a wart, at other 



