64 



HISTORY OF CRUSTACEA. 



Chap. YII. 



The youngest larva of the Schizopod genus Eu- 

 phausia observed by Claus, stands very near the 

 youngest Zoea of our Prawns ; but whilst its anterior 

 antennae are already biramose, and it therefore appears 

 to be more advanced, it still wants the middle maxilli- 

 pedes. In it also Claus found the heart furnished with 

 only a single pair of fissures. Do not Nauplius-like 

 states in this case also precede the Zoea ? 



Fig. 33.18 



The developmental history of Mysis, the near re- 

 lationship of which with the Shrimps and Prawns has 

 recently again been generally recognised, has been 



respect resemble the larva of Sergestes found by Claus near Messina 

 (Zeitschr. für Wiss. Zool. Bd. xiii. Taf. 27, fig. 14). This unusual length 

 of the antennse leads to the supposition that they belong to our com- 

 monest Prawn, which is very frequently eaten, and is most nearly allied 

 to Peneus setiferus of Florida. Claus"s Acanthosoma (I. c. fig. 13) is like 

 the yoimger Mtjsis-iovm of the larva figured by me in the ' Archiv für 

 Naturgeschichte,' 1836, Taf. 2, fig. 18, and which I am inclined to refer 

 to Sicyonia carinata. 



^8 Fig. 33. Older larva produced from the Zoea represented in fig. 32. 

 The last segment and the last two pairs of feet of the middle-body are 

 wanting. Magn. 20 diam. 



