304 
ZOOLOGICAL LITERATURE. 
VII. They approach the Cladoceruj 
1. In the small number of appendages. 
2. In the unsegmented tail (pleon). 
VIII. They stand bet\Yeen the Phyllopoda and Cladocera 
In the manner of development. 
IX. They differ from the Phyllopoda and the Cladocera^ 
1. In being organized for a parasitic life (vide III. & IV.). 
2. In their appendages wanting the complete branchial supplement. 
3. In the tail being transformed into a branchial lamina. 
4. In the difference of the generative apparatus, especially as to the 
receptacula seminis. 
6. In the external escape of the ovum immediately it leaves the ovary. 
6. In the absence of parthenogenesis. 
The consideration of these points leads the author to the 
conclusion that it is impossible that the Argulidae should be 
included among the families of the Copepoda, but that there are 
some important points which appear to justify their being classed 
with the Branchiopoda. . He considers Argulus to be a parasitical 
Branchiopod having some affinity with the Phyllopoda and the 
Cladocera, classifying the Branchiopoda thus : — 
I. Phyllopoda. Eyes compound, more or less separated ; 10-60 pairs of 
feet j metamorphosis complete. Free swimmers. 
1. Branchiopodidce j 2. Apodidce ; 3. Limnadiidce j 4. Nebaliidce. 
II. Cladocera. Eyes compound, united in one j 4-6 pairs of feet ) no meta- 
morphosis. Free s’vyimmers. 
1. PaphniidcB. 
III. Branchiura. Eyes compound, separated \ 4 pairs of feet j metamor- 
phosis incomplete. Parasitic. 
1. Aryulidce. 
He then gives in Latin a more detailed description of the 
Branchiura, and classifies the species in the following genera : — 
Gen. 1. Argulus, Muller (1785). Maxillipedes primi paris in adult, cotyle- 
dones formantes. 
a. Pedes flagello carent. Stimulus ante siphonem adest. Sipho mandi- 
bulas'et maxillas continet (Agenor, Risso). 
1. A. purpureus (Risso) j 2. A. giganteus (Lucas). 
j8. Pedes parium 1‘ et 2’ flagello instruct!. Stimulus adest. Sipho man- 
dibulas et maxillas continet (Argulus, Miiller^. 
3. A. foliaceus (Linn.) j 4. A. coregoni (Thor.) ', 5. A. pugettensis 
(Dana) ; 6. A. catostomi (Dana and Herrick). 
y. Pedes parium 1‘ et 2* flagello instruct!. Stimulus adest. Sipho mandi- 
bulas tantum includit (Camulus, Thorell). 
7. A. nattereri, Hell. 
h. Pedes parium 1‘ et 2‘ flagello instruct!. Stimulus nullus P Sipho ? 
8. A. salmini (Kr.) j 9. A. creomidis (Kr.) j 10. A.funduli (Kr.) ; P 11. 
A. alosce (Gould) ', P 12. A. elongatus (Hell.). 
