48 



THE APODID^ 



PART I 



their muscles (see Fig. 12, p. 55) that what the 

 gnathobases held between them would be rapidly 



The disappearance of 

 on the most anterior 



forwarded towards the mouth. 



the gnathobases, excepting 



trunk limbs — the maxilllpedes — In the majority of 



modern Crustacea, Is explained by a change In the 



manner of life. As the trunk limbs became more and 



r""ii,, 



Fig. 10.— The last rudimentary trunk limb (Z, product us), \ mm. in length. Lettering 

 as before. It is seen to be a typical Phyllopodan limb. 



more purely locomotory organs, such as ambulatory 

 legs, and as other methods of capturing prey were 

 acquired, the ventral parapodia would degenerate, not 

 only from having lost their function, but as positive 

 hindrances to the free movement of the limbs. 



The most distal appendage, on the first limb of 

 Apus, Is a probably functlonless scale (Fig. 9), and in 

 the following limbs It Is a toothed claw (Fig. 4), while 



