The venerable Spath said (a long time ago):
"Variations in the size of the protoconch, however, still occurred in the Upper Cretaceous, as they occurred in the Devonian, without any obvious explanation, except perhaps the extremely loose coiling in Anarcestes as in Gaudryceras, with their large protoconchs. Otherwise the protoconch in Ammonoidea is dependent on the shape and coiling of the later whorls as much as in Nautiloidea and varies too much in goniatites, for example, to be of systematic importance. Even if not going so far as Schindewolf and insisting on the omission, henceforth, of the initial chamber from the diagnoses of the two orders Ammonoidea and Nautiloidea, it must be admitted that it has ceased to be an element of decisive importance."
Kevin, I've had another close look at the specimen with the tiny orthocones and cannot convince myself of lobes in sutures, or even clearly see any sutures at all. I remember certain layers in the Early Devonian Hunsruckschiefer having masses of little dacryoconarids - do some of those have smooth shells and protoconchs? On the other hand, I've just found some illustrations from Bandel et al. (1983) showing Devonian teuthids, with hatchling Protaulacoceras being a very good match for my examples.