SUPER-ORDER V MALACOSTRACA 661 
a frontal spine (rostrum) between the compound pedunculate eyes. Gulls borne on or near 
the basal joints of maxillipeds and legs, and enclosed in a branchial chamber formed by a 
downward expansion of the carapace on either side. 
No Palaeozoic Crustacean is known which displays typical Decapod characters, and 
it is possible the group did not become differentiated until the Trias, where the first 
undoubted remains occur. Their forerunners, however, are evidently to be sought for 
amongst the collective forms already cited under the Schizopoda. Although a division 
into the sub-orders Macrura and Brachyura is not strictly natural, yet it is of certain 
convenience to the palaeontologist. The so-called Anomura, which are very rare in 
the fossil state, are distributed between these two sub-orders. 5 
Sub-Order A. MACRURA. Latreille. (Lobsters, Shrimps, Prawns.) 
Abdomen strongly developed, as long or longer than the cephalothorax, and never 
infleced beneath the latter ; rt is provided with four to five pairs of abdominal feet, and 
the swimmerets of the sixth segment form with the telson a strong caudal fin. The third 
par of maxillipeds are long and slender, and do not completely cover the preceding ones. 
(1) The family Carididae or prawns have a usually compressed body covered by a 
delicate cuticula; legs long and slender, some or all of the pairs chelate; rostrum 
usually well developed, and 
large antennal scale present. 
Undoubted Caridids are repre- 
sented in the Lithographic 
Slates of Bavaria by the 
following genera :— Penaeus, 
Fabr. (Fig. 1384); Acantho- 
cheirus, Oppel; Bylgia, Ca 
Drobna, Dusa, Aeger (Fig. TSS 
1385), Blaculla, Udora, Fic. 1384. 
Hefriga, Elder, Miinster ; and Penaeus Meyeri, Oppel. Lithographic Slates; Solenhofen. 1/y, 
Udorella, Oppel. Pseudo- 
erangon, Schliiter, and Oplophorus, Milne-Edw., occur in the Upper Cretaceous of 
Westphalia. Homelys, v. Meyer, and Palaemon, Fabr., are Tertiary genera, the latter 
also Recent. 
(2) The Eryonidae have a thin, broad, and depressed carapace, with a median 
longitudinal keel; antennal scale small; four anterior pairs of feet chelate ; caudal fin 
large. Tetrachela, Reuss, from the Upper Trias of Raibl, is one of the oldest known 
Decapods. Hryon, Desm. (Fig. 1386), ranges from the Lias to Cretaceous, exquisite 
examples being found in the Lithographic Slates. Polycheles, Heller, and Willemoesia, 
Grote, are recent deep-sea forms. 
(3) In the Palinuridae (Loricata) the body is stout, antennal scale small, and all 

Boston Soc. Nat. Hist., VII.), 1868.—Vvritsch, A., Ueber die Callianassen der béhmischen Kreide 
(Abhandl. Bohm. Ges. Wiss. [6], I.), 1868.—Carter, J., On Orithopsis Bonneyi (Geol. Mag. [1], 
IX.), 1872.—Decapod Crustaceans of the Oxford Clay (Quar. Journ. Geol. Soc., XLII.), 1886.— 
(Ibid. LIV.), 1898.— Woodward, H., Macrurous Crustacea, etc. (ibid. XXIX., XXXII.), 1872-76.— 
Tribolet, M., Descriptions des Crustacés du terrain neocomien (Bull. Soc. Geol. France [3], IL., 
IIL.), 1874-75.—Bittner, A., Brachyuren des vicentischen Tertiiirgebirges (Denkschr. Akad. Wiss. 
Wien., XXXIV., XLVI.), 1877-83.— Winkler, T. C., Etudes sur les genres Pemphix, Glyphaea, et 
Araeosternus (Archiv. Museé Tyler [2], I.), 1883.—Ortmann, A. #., Das System der Decapoden- 
Krebse (Zool. Jahrb. Syst. Abth., [X.), 1896.—On Linuparus in the Upper Cretaceous of Dakota 
(Amer. Journ. Sci. [4], IV.), 1897.—Moericke, W., Die Crustaceen der Stramberger Schichten 
(Palaeontogr. Suppl., Il.), 1897.—Zérenthey, E., Ueber die Brachyuren der pal. Sammlung des 
Bayerischen Staates (Termeszetrajki Fiizetek Budapest, XXI.), 1898.—Beitrag zur Decapodenfauna 
des ungirischen Tertiars (ibid. ; also in Math.-naturw. Ber. aus Ungarn XIYV.), 1898. 
