Professor C. E. Beecher — On Stylomirus Lacoanus. 485 



the characteristic surface markings. Its elliptical or ovoid section 

 without any flattening of the epiraera, the very considerable over- 

 lapping of the joints, and the configuration of the suture, are more 

 strongly indicative of the nature and requirements of a limb than of 

 abdominal segments. 



The Belief Model. 



In this restoration the animal is represented as lying on a slab, 

 with the entire dorsal surface exposed. The cephalothorax has an 

 axial length of 25 cm. and a width of 22 cm. 



The chelate antennae were doubtless carried in a folded position, 

 as in most related genera, and seldom were visible from the dorsal 

 side. They are, therefore, not shown. The three pairs of short 

 gnathopods, serving partly as swimming organs, are seen extending 

 outward from the antero-lateral margins of the cephalothorax. 

 Several of their distal joints are each provided with a pair of flat, 

 ridged, spinous processes, and a similar spine at the termination of 

 the limb. 



The two pairs of great crawling feet extend outward and backward 

 from the postero-lateral margins of the cephalothorax. The anterior 

 pair expose 109 cm. of length, and the posteror pair about 108 cm. 

 The elements of the limbs are represented as grooved, as this 

 character seems necessary to give the needed strength to long 

 slender joints, and also because a similar conformation is present 

 in S. Beecheri. 



The abdomen measures 30 cm. in greatest width at the fifth 

 segment, and 66 cm. in length exclusive of the telson. The posterior 

 abdominal segments are represented without detachable epimera, as 

 this feature is not as yet known to be constant for the genus, although 

 present in some species. 



The telson spine agrees proportionally in length with the same 

 member in S. Logani and "S". Poioriei as described by Woodward,^ 

 and was given a slight upward curvature as in Limulus. It 

 measures 54 cm. in length and 75 cm. across at the proximal end. 



Altogether the animal as restored has a length of nearly five feet 

 (147 cm.), and with the legs extended it would measure about eight feet 

 (242 cm.) across. 



It is not intended to claim any high degree of accuracy for this 

 restoration, but merely to represent in some graphic form an animal 

 approximating in size and character an individual of the species 

 Stylomirus Lacoanus. Its size alone was the chief incentive for 

 attempting a reconstruction, and some sacrifice of exact detail may 

 well be allowed in order to make any presentation of this magnificent 

 arthropod. 



' Loc. cit. 



