EXPLANATION OF THE PLATES. 385 



Fig. 



11. One of the antennae of ditto, viewed laterally and on 



the outside. 



12. Ditto, ultimate segment of. 



13. Body of the above complemental male, consisting of 



the thorax supporting the four pairs of limbs, 

 and of the terminal abdominal lobe, 



14. Small portion of the outer integument of the com- 



plemental male, as seen with a ^th of an inch 

 object glass. 



15. /Scalpellum vulgare (hermaphrodite), magnified three 



times. 

 (a, a.) Complemental males. 

 {b.) Rostrum, of which a separate enlarged figure 



(b') is given. 



15 a. Scutum of the hermaphrodite Scalpellum vulgare, 

 internal view of. 

 (a.) Fold on the occludent margin. 

 (d.) Pit for the adductor muscle. 



TAB. VI. 



1. Scalpellum ornatum, (female, magnified seven times.) 

 Id. „ „ Upper latus, viewed internally. 



\b\ ,, „ Scutum of full-grown specimen, 



viewed internally, much mag- 

 nified. 

 {a.) Depression for the adductor 



muscle. 

 {b.) Depression for the reception 

 of the male. 



\c. ,, ,, Scutum of half-grown specimen, 



viewed internally, much magni- 

 fied, on same scale with fig. lb '. 

 The depression (b) for the re- 

 ception of the male is here seen, 

 in almost the first staaesSTtf, 

 formation. ,'•' ' . 





