St. Andrews Marine Lahoratory. 483 



brownish by transmitted light. The snout often shows a slight 

 furrow nearly opposite each eye. On the summit of the prge- 

 stomium, just in front of the nuchal fold, are a smaller pair of 

 eyes placed near each other. Occasionally a pigment speck or 

 two exist in front of these. 



The armature of the proboscis (PI. XIII. fig. 6) consists of 

 a pair of dark brown or blackish, strongly curved^ and sharp- 

 pointed maxillge, behind which an acute posterior process 

 projects. Six denticles, which probably represent the dental 

 plates of allied forms, occur beneath and in front of these, each 

 having a somewhat hoof-shaped outline, the free edge ante- 

 riorly being finely denticulated. They diminish in size from 

 before backward, the last having a long and slender process 

 which reaches the posterior border of the maxillae. The 

 younger examples, as in the figure, have a smaller number of 

 denticles. The mandibles have a process or tooth on the 

 inner edge anteriorly, and the external region or spur is 

 minutely crenate in front. The shafts are gently curved, like 

 the letter f^ and have a wing-like appendage immediately 

 behind the anterior region. 



Dorsally each foot presents a short cirrus, and ventrally a 

 somewhat larger one. A long and conspicuous setigerous 

 process occurs between these just above the ventral cirrus. 

 The dorsal bristles (PI. XIII. fig. 7) consist of two or three 

 long and slightly curved simple bristles, the tips of which 

 are somewhat flattened and slightly hooked. The ventral 

 series are compound, the terminal pieces being apparently 

 simple and slightly hooked (PI. XIII. fig. 8). A strong spine 

 supports the fleshy part of the foot. 



At first sight it was supposed that the species just described 

 corresponded with a form discovered by Prof. Langerhans in 

 Madeira, and which he has termed Staurocephalus minimus ■^. 

 The latter, however, appears to diifer in the greater length 

 (antero-posterior diameter) of the head and in the minute 

 structure of the jaws and bristles. Thus the maxillae in the 

 foreign species wholly difier (if the figures of Langerhans are 

 to be trusted) in appearance, and none of the pectinate pro- 

 cesses he shows are to be found in the dental apparatus of Stauro- 

 cephalus Siherti. So far as could be made out also the tips 

 of both dorsal and ventral bristles are simply hooked and not 

 bifid, as in the species from Madeira, Langerhans mentions 

 that the Lacydonia miranda of Marion and Bobretzky f, from 

 the Gulf of Lyons, presents certain resemblances to his 



* Zeitschr. f. wiss. Zool. Bd. xl. p. 257, pi. xv. fig. 16. 

 t Ann. des Sc. Nat. 6^ ser. ii. p. 57, pi. vii. fig. 17, &c 



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