PACKAKD.] MORPHOLOGY OF PHYLLOPODA. 389 



eggs in place in the different genera of the family. On acconnt of its 

 holding or keeping the eggs in place, this portion of the flabellnm may 

 be called the oviger. These ovigers are best developed functionally near 

 the end of the body, the eggs being grouped near the end of the dorsal 

 edge of the shell. 



In Estheria the gnathobase (Plate Y, figs. 6, 7 c?^, 7a) of the anterior 

 baenopods is rather more complicated than in Limnetis. Fig. 7a repre- 

 sents one highly magnified. The inner edge is beset with rather stitf 

 simple setae, while those on the outer edge are thick at base, beyoud 

 slender and setulose. Similar hairs are seen on the gills (flabella) of the 

 Ostracoda {Gypris, &c.) and in the endopodal as well as the exoj)odal 

 portion of the feet of the Gladocera {Baphnia, &c.). 



In Estlieria the second, third, and fourth endites are equal in size, 

 while the fifth is long and narrow, and the sixth shorter and broader, 

 scalloped on the inner edge ; the gill is large, the oviger long and narrow, 

 while the lower lobe of the flabellnm [br") exactly repeats in form the 

 sixth endite. 



In Eulimnadia (Plate VI) the female endites 2-5 are quite equal in size 

 and appearance while the sixth is finger-shaped in outline, like the end 

 of the flabellnm, and the gill {br) is very large. The hand of the male 

 differs from that of Estlieria in lacking the thumb-like growth on the 

 fourth endite (en.'*) ; while the diminutive flabellnm {br") does not reach 

 to the base of the fourth endite, and the dorsal end of the flabellnm is 

 rudimentary. 



Turning now to the first male basnopod of Limnetis, while the exite 

 and their basal endites have undergone no modification, the three outer 

 endites are curiously changed into a hand-like organ. The fourth 

 endite is a long and broad lobe, with two rows of short, basally stout 

 setaes. This lobe we call the comb or pecten (Plate II, tig. 2 ; Plate I, 

 fig. 5). Fromthedistalend arises a thumb-like moveable process provided 

 externally with setas. The fifth endite is modified into a curved fore- 

 finger-like i)rocess with a few terminal setae opposing the thumb ; while 

 the sixth endite forms a still longer and much largerfinger, which is bent 

 upon the entire hand and is not setose. These lobes arise from a distal 

 chitinous specialized portion, which may be called the hand or manus, 

 with its two " fingers" opi)Osing the "thumb." 



The second pair of b8enoi)ods are in Estheria and EuUmnadia modified 

 in the same manuer (Plate V, tig. 6) ; the chief diflerence being the 

 narrower fourth endite, whose setae are broad, stout, lancet-like (Plate 

 XXV, tig. 3b). In the second pair of feet of Estheria the fifth endite 

 differs from that of the first pair, and also the single pair of Limnetis, 

 in being two-jointed (Plate XXV, fig. 3tt, Z^); the end of the distal joint 

 being slightly bulbous. 



Glaus represents the sixth endite or "claw" of Limnadia stanJeyana 

 from Australia as bearing a sucking disc; a similar disc occupies the 

 same position in Limnadia africanu Brauer and L.mauritiana Guerin. 

 It thus seems to occur in certain species of Limnadia^ but not in the 

 American genus EuUmnadia. 



Turning now to the api^endages of the Apodidw, we find it comx)ara- 

 tively easy to homologize the diflereut parts with those of the Limna- 

 diadce, though, as a whole, the apodid foot is the most peculiar, sni 

 generis, of any x^hyllopods. The limbs of the European A23us have been 

 studied with care by Professor Lankester in his paper on the appendages 

 and on the nervous system of Apus cancriformis ; and he has briefly 

 compared them with the published drawings of other phyllopods, as 

 well as of the Decai3ods. He regards the axial portion of the limb of 



