16 D. M. S. Walaon — On Limulus Woodicordi, Loicer Oolite. 



other anteriorly, and then rather suddenly separate before quite 

 touching ; they then shortly die out. The glabella is divided 

 transversely by two grooves, one a little behind the point of minimum 

 width, the other half-way between that and the back of the 

 carapace. 



In the same line as this last groove are the lateral eyes. They are 

 situated about three times the width of the glabella apart and stand 

 up above the general level, just as in Limulus Polyphemus. Their 

 structure cannot be seen. 



On the right side is a trace of a small projection continuing the line 

 of the eye ridge at the extreme back of the carapace. The carapace 

 is strongly arched from side to side and is quite uncrushed. 



The measurements are as follows : — 



cm. 



Width between genal aimles . 7'64 



Greatest width . . . . . . . . .8*1 



Length on median line . . . . . . . . 4'2 



"Widtli on glabella at back . . . . . . . 1 'o 



Width of attachment of abdomen ...... 4'2 



Distance of eye in front of line of attachment of abdomen . 1 • 1 



Distance apart of lateral eyes . . . . . .4-2 



Depth of carapace at back . . . . . . . 1-S 



There can be no doubt that the carapace described above is that of 

 a Limulus. Its resemblances to the recent L. Polyphemus are 

 extremely striking, the differences being slight variations in certain 

 l^roportions. 



In L. Polyphemus the carapace is longer than wide, and the 

 articulation of the abdominal dorsal shield is wider than in the British 

 form. The lateral eyes are placed somewhat further forward, and the 

 glabella is not so obviously divided by transverse grooves. 



The British specimen differs considerably from L. Walchi, the 

 species which occurs in considerable abundance in the Solenhofen 

 Slate ; in Z. Walchi the glabella is not divided by transverse grooves, 

 and the lateral eyes are apparently not mounted on a distinct projection 

 as they are in the new species. On the other hand, the upper oolitic 

 species has the same downturned edge of the lateral parts of the 

 posterior edge which is such a feature of the jS'orthamptonshire 

 species. L. syriacus from the Cretaceous of Hakel, Syria, differs 

 greatly in the general shape of the carapace and in the crimping of 

 the very narrow glabella. 



There remain only Limulus Lecheni from the Oligocene of Tenchern 

 near Merseborg, which is a large species ; two small and simple 

 species from the Trias of Germany, and one from the European 

 Khaetic. These last are forms with a simple carapace of small size. 

 It thus appears that the Doddington specimen is distinct from all 

 known species, and I suggest that it be called Limulus Woodwardi 

 after Dr. Henry Woodward, to whom our knowledge of the British 

 Merostomes is so largely due. 



