Fig. 1. 
Fig. 11. 
Fig. 12. 
Fig. 13. 
PLATE XVI. [Prats 27.] 
ANATOMICAL ILLUSTRATIONS FROM RECENT CR OUSTACEA., 
Ca:anus (spec. ?), magnified about twelve times. 
In this and the succeeding Figures the Letters have the same Stgnification. 
I’, eyes. 
II’, antennules. 
III’, antenne. 
IV’, mandibles. 
V’, first maxillae. 
VI’, second maxillz. 
Ib. ep., conjoined labrum and epistoma. 
mt., metastoma. 
R., rostrum. 
I, 2, 3, 4, 5, 6, thoracic appendages. 
- Ventral view of the oral aperture, with the surrounding parts ; the palp of the left 
mandible and the left first maxilla are omitted. 
. Right mandible. | 
- Right first maxilla. | All magnified to the same scale, and the long sete in all 
Right second maxilla. | cut short. 
. First thoracic limb. 
. Thoracic swimming limb, the left half only being fully represented. 
. Coryceus laticeps (?), dorsal view ; much magnified. 
. Ventral view of the anterior part of the carapace of the same. 
. Right mandible of Mebalia Geoffroy. 
Ventral view of the parts about the mouth in a Ponte//a. 
Ventral view of the parts about the mouth in an embryonic lobster (Homarus) not 
yet hatched, showing the large proportional size of the labrum and metastoma. 
Ventral view of the parts about the mouth in L2me/s. 
Figs. 14, Ventral, and 15, dorsal, view of the left posterior thoracic limb, specially modified 
Fig. 16. 
for swimming, of A/atu?a, a brachyurous Crustacean.* 
The corresponding limb of Portzsus puber. 
Figs. 17, 18. Lateral and dorsal views of Cuma Rathkzi ; much magnified. 
Fig. 19. 
Sapphirina gemma, after Dana. 
* T have added these figures of limbs, specially modified for natation, in some Swimming 
Crabs, in order to show their similarity to those appendages of Prerygotzs which served the 
same purpose.—T. H. H. 
