768 



ARTHROPODA 



PHYLUM VII 



Division D. HOPLOCARIDA Caiman. 



Order 1. STOMATOPODA Latreille.i 



Carapace small, leaving at least four of the thoracic somites distinct and wn- 

 covered; with a movable rostral plate anteriorly. Eyes pedunculate. Eyes and 

 antennules home on movable segments of the head. First five pairs of thoracic limbs 

 sub-chelate, the second pair very large. Abdomen large and depressed, ending in a 

 tail-fan. First five pairs of abdominal appendages carrying tufted gills. 



The existing Stomatopods form a very homogeneous group, within which 

 onljT^ one family (Squillidae) can be recognised, while many of the genera are 

 separated by comparatively slight differences. Representative forms are 

 Squilla Fabr. ; Lysiosquilla and Pseudosquilla Dana ; Gonodactyhis Latreille ; and 

 Coronida Brooks. Modern Stomatopods are exclusively marine, the adults 



generally inhabiting burrows 

 in the sand or mud of the sea- 

 bottom in shallow water, chiefly 

 in the tropics, but extend- 

 ing also 50 degrees on either 

 side of the equator. Many 

 species seem never to wander 

 far from their burrows, into 

 which they retreat with great 

 rapidity when alarmed. The 

 larval stages, on the other 

 hand, are exclusively pelagic, 

 of glass-like transparency, and 

 occur in great numbers in the 

 plankton of the warmer seas. 

 All the Stomatopods appear 

 to be of active, predatory 

 habits. They range in size 

 approximately from 38 to 

 Fig. 1495. 340 mm. 



Sculda pennata Mnnst. Upper Jura ; Bavaria, yl, £, Dorsal The existence of Stoma- 



views, Vi and 3/i. C, Ventral aspect, s/i- «, e, First and second f^nnds; in PnlpnymV timps la 

 pairs of antennae (after Kunth). topoUS in raieOZOlC timCS IS 



still doubtful. Necroscilla 

 Woodward, from the English Coal Measures, is based on a fragment of the 

 abdomen and telson. Perimerturns Peach, from the Carboniferous of 

 Scotland, shows several features, such as the massiveness of the abdomen and 

 the movable rostral plate, that suggest an affinity with this order. In the 

 Kimmeridgian of Solenhofen undoubted Stomatopods occur, some of which 

 are even referred to the Eecent genus Squilla Fabr. (also known from 



1 Literatiu'e : Munster, G. Graf zu, Beitrage zur Petrefaktenkiuide. Parts iii. and v., 1840- 

 1842. — Mark, W. von der, and Schlutcr, C, Neiie Fische uud Krebse aus der Kreide von Westphalen. 

 Palaeontogr., 1868, vol. xv. — Kunth, A., Uber wenig bekannte Crustaceen von Solenhofen. 

 Zeitschr. Deutsch. Geol. Ges., 1870, vol. xxii. — Woodward, II., Contributions to the knowledge of 

 fossil Crustacea. Quart. Journ. Geol. Soc, 1879, vol. xxxv. — Brooks, W. A'., Report on the 

 Stomatopoda. Scient. Results Challenger Exped., Zool., 1886, vol. xvi. — Miers, E. J. On the 

 Squillidae. Ann. Mag. Nat. Hist., 1880, ser. 5, vol. v. 



