Not a pattern that I have come across before, Chris, but definitely Sowerby pattern 1349 - shown on the extreme right of the bottom row on page 6 of pattern book IX (1882).
The lozenge for 20 March 1878- Parcel 7 covers a bundle of 5 design registrations which, I think, correlate with pattern numbers as follows:
RD 319585 vase pattern 1298 p6, IX (1882)
RD 319586 biscuit jar
RD 319587 plate pattern 1339 p39, XI (1885)
RD 319588 two-handled basket pattern 1297 p5, IX (1882) from Cottle
RD 319589 vase pattern 1299 p6, IX (1882) from Cottle
I have reference photos for all the designs in this bundle EXCEPT for RD 319586, so I would have assumed that pattern 1349 corresponded to the 'biscuit jar' RD 319586 -

?
I will attach pics of the known pattern number - RD number correlations in this post and the follow-ups
Fred.