Vol. 62.] OMOSPIBA, LOPHOSPIBA, AND TURBIT031A. 571 



Dimensions. — Length = 18 millimetres; width of the penul- 

 timate whorl = 10 mm. 



Locality and Horizon. — Woodland Point (Ayrshire), in rocks 

 of Middle Llandovery age [Lapworth], 



In the preparation of this paper I must acknowledge how greatly 

 I am obliged to Mrs. Robert Gray, Edinburgh, Prof. Hughes, the 

 Committee of the Bristol Museum, and the Geological Survey of 

 Scotland for the loan of specimens. I desire also to express my most 

 sincere thanks to Dr. A. Smith Woodward, Dr. Scharff, Mr. E. 

 B. Newton, Dr. Kitchin, and Mr. H. A. Allen, for affording me 

 every facility in studying the different collections under their care, 

 and to Mr. C. D. Sherborn for assistance in looking up references. 

 I am also deeply indebted to the late Mr. J. G. Goodchild, F.G.S., 

 for helping me in many ways. 



EXPLANATION OF PLATES XLIII & XLIV. 

 Plate XLIII. 



Figs. 1 & 2. Omospira oriental is, sp. nov. Fig. 1. Internal mould, X 1^. 

 Fig. 2. Wax-impression from a portion of the external mould of 

 the same specimen, X 2. Fig. 2 a. Outline of fifth whorl from the 

 base of the same external mould, drawn from a wax-impression, X 10. 

 Starfish Bed, Thraive Glen (Ayrshire"). Gray Collection. 

 3-5. Lophospira gyrogonia (M'Coy). Fig. 3. Specimen marked as 

 type, internal mould, X 4. Fig. 4. Side view of another internal 

 mould, X 4. Yspvtty Evan (Denbighshire). Sedgwick Museum. 

 Cambridge. Fig. 5. Back view, shell compressed obliquely, showing 

 lines of growth, X 4. Shallock Mill (Ayrshire). Gray Collection. 



Fig. 6. Lophospira excavate/, sp. nov. Front view, X 2. Minuntion (Ayrshire). 

 Gray Collection. 

 7. Lophospira trispiralis, sp. nov. Front view, X 6. Shallock Mill (Ayr- 

 shire). Gray Collection. Fig. 7 a. Back view of body-whorl of 

 another specimen, X 8. Drummuck (Ayrshire). Gray Collection. 



Figs. 8-10. Lophospira instabilis, sp. nov. Fig. 8. Side view of broken internal 

 mould, showing sinus in outer lip and lines of growth, X 3. 

 Fig. 8 a. Portion of penultimate whorl drawn from a wax-impression 

 taken from an external mould of the same specimen, showing tri- 

 lineate band with the threads nearly equal, x6. Fig. 9. Front view 

 of another specimen showing the trilineate band with central thread 

 the strongest, X 3. Fig. 9 a. Portion of whorl showing band 

 enlarged, X 6. Fig. 10. Back view of internal mould of a larger 

 specimen, X2. Thraive Glen (Ayrshire). Gray Collection. 

 11 & 12. Lophospira Sedgwiekii, sp. nov. Fig. 11, Back view drawn 

 from a wax-impression, X 3. Mullock Quarry (Ayrshire). Gray 

 Collection. Fig. 12. Front view, drawn from a wax-impression, 

 X 3. Mullock Quarry. Sedgwick Museum, Cambridge. 



Plate XLIV. 



Fig. 1. Lophospira ferruginea, sp. nov. Back view, x 4. Big. 1 a. Portion of 

 whorl, X 8. Ardmillan Brae (Ayrshire). Gray Collection. 

 2. Lophospira bicincta (Hall). Back view, X 2. Balclatchie (Ayrshire). 

 Gray Collection. 



Figs. 3 & 4. Lophospira bicincta. var. scotica nov. Fig. 3. Back view, x 2. 

 Fig. 4. Front view of another specimen, X 2. Balclatchie (Ayr- 

 shire). Gray Collection. 



