Note 5 — Chapter VII · STRUCTURE OF THE HEART IN THE EDRIOPHTHALMA.

The oldest observed larvæ (see Fig. 33) are characterised by the extraordinary length of the flagella of the outer antennæ, and in this 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 antennæ leads to the supposition that they belong to our commonest Prawn, which is very frequently eaten, and is most nearly allied to Penëus setiferus of Florida. Claus’s Acanthosoma (l. c. Fig. 13) is like the younger Mysis-form 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.