10!> 



which commence at the umbilicus, curve a little forwards and then gently 

 backwards across the sides, after which they form a series of elongated, 

 beak-like processes with conciive sides in passing over the periphery, 

 Underneath the shell there arc seven constrictions or grooves on the east 

 of the outer whorl. These are the remains of former lips, whose curves 

 are precisely pai-allel with the flexuous stride of the test. Septation 

 unknown. 



Greatest diameter of an average sized individual, twenty-seven lines; 

 width of umbilicus of the same, not quite two linos and a-half Maximum 

 width of the aperture, ten lines and a-half; height of do., outside of the 

 emargination, fourteen lines ; depth of the emargination, six lines and 

 a-half. 



Sucia Islands, in Division A.; J Eichardson, 1874. Nine good 

 specimens. 



This species appears to be more closely allied to Ammonites subalpinus* 

 D'Orbigny, and A. diphylloides, Forbes, then it is to A. ramosus or A. 

 Velledce. Besides having much flatter shells than A. Selivynianus, the 

 casts of A. ramosus and A. \ elUd'.e are devoid of periodic grooves or constric- 

 tions and their test is finely ribbed. Casts of A. subalplnus and A. 

 diphyUcides ave impressed hy transvei'se furrows at distant intervals, but 

 in these species the radiating strise of the test and the furrows beneath it 

 are not developed on the siphonal edge into the beak-like processes which 

 Are characteristic of A. Sdwynianus. 



Ammonites Indra, Forbes. 



Plate 13, figures 2 and 2a. 



Ammonites Indra, Forbes.— Trans. Geol. Soc, Lond., 184G, Vol. VII. p. I05.pl. II, fig 7. 

 " " " Stoliczka Crct. Ceph. of S. India, p. 112, pi. 58, fig. 2. 



The exquisitely preserved Ammonite figured on plate 13 was found by 

 Mr. Eichardson imbedded in a large concretion or nodule from the Middle 

 Shales (Division D.) of the Noi-th-West side of Hornby Island, in the 

 summer of 1871. The shell is rather more than five inches in diameter, 

 and although its siphonal lobes and saddles are everywhere covered by 

 the test, it is in much better condition than any of the Indian specimens 

 of A. Indra described by Forbes or Stoliczka, with whose characters it 

 agrees in every essential particular. The faint transverse furrows of 

 the surface are, perhaps, proportionally moi-e distant in the Hornby Island 

 Ammonite than they are represented to be in Stoliczka's figures of A, 

 Indra, but this is doubtless only an individual peculiarity. 



