of the floriated knob on the how is the same. The main difference is in the intricate and somewhat confused pattern which covers the trumpet-shaped head, and which probably also owed its origin to a design such as decorates the head of the Birdlip brooch. To form this pattern, the surface of the metal is cut out and the hollows filled with enamel of different colours-blue, yellow and red. The collar at the base of the terminal loop on the head is solid. Like the rest of the brooch, it is ornamented with enamel. Fig. 15, which is in good preservation, came from one of the chambers at the rear of the Principia. It has no enamel decoration. The 'find-spot' suggests that it is probably later than any of the members of the group already dealt with. Fig. 16 was found in the upper levels at the Baths.
One or two pairs of these brooches have come to light in the north of England, associated with coins. The set from Backworth was alluded to above. Another pair, made of silver and decorated with enamel, was discovered at Chorley, Lancashire, with a chain and a series of coins dating from the reign of Galba to that of Hadrian, A.D. 69 to 138. In the Backworth brooches the trumpet-shaped head has broadened out, and the wire collar at the base of the terminal loop has coalesced with the head, while the loop itself has become fixed and heavy. As already noted, all of these features are suggestive of the degradation which so often precedes the extinction of a type, a process still further advanced in the case of the great Aesica fibula,[1] which is attributed to the beginning of the third century.
Figs. 17 to 23 (Plate LXXXVI.) are nearly akin to the Lamberton Moor fibula described above, but all of them show signs of development which prove them to be later. Thus the spiral spring has disappeared, having given place to a hinge, and the collar at the base of the terminal loop on the head has become an integral part of the body. As a rule, too, the stud no longer serves any useful purpose, but retains its place solely as a survival. The vertical lines incised on the cross-bar are a reminiscence of the spiral spring. Here again we have a common British type which occurs sporadically on the Rhine. Two of these fibulae, decorated with enamel and attached together by a chain of woven strands of fine bronze wire, were discovered in a tall glass vessel in a grave in the Maximinstrasse in Trier in 1878. The glass vessel is attributed to the end of the first century. In no case did the circumstances under which the Newstead examples of this particular group were found afford conclusive evidence as to date. All of them were
1 Archaeologia, vol. lv. p. 181, fig. 4.
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