6 TYPE AMMONITES— III August 



1919 



technical term by (i) geological, (2) artificial. Then Ammonites which 



are small by growth require much further analysis. The following 



technical terminology is proposed, applicable also to other organisms : — 



Colomorph — small because reduced by breaking off of outer whorls 



by geological or artificial agents (k6\os, docked). 

 Micromorph — small by growth — auxologic diminutive (Hudleston, 

 Jur. Gaster. Pal. Soc. 1888, 61) — subdivided : — 

 Brephomorph — small because young, ontogenetically immature 



— baby or foal stage (fy>e'<£or, a foal). 

 Anamorph — small because phylogenetically immature — 

 Eohippus stage — Arnioceras miserabile, flavum, etc. stage 

 (Ana — of Anagenesis). 

 Phaulomorph — small because stunted, phylogenetically mature, 



but under-sized — Donkey stage (<£avA<», paltry, mean). 

 Catamorph — small because phylogenetically degenerate (? tarpan 

 stage) ; Schlotheimia lacunata (and allies) stage ; Criocone 

 stage (Cata- of catagenesis). 

 Nomomorph — of normal, average, or customary size ; hackney horse 



stage {vofios, custom). 

 Megalomorph — of large size ; shire-horse stage ; giant stage (ptyas, 



great). 

 When the distinction between phaulomorphs and catamorphs is in 

 doubt, it is suggested that they be referred to as nannoids (vdwos dwarf). 

 The distinction is that the former are presumed to be derived directly 

 from anamorphs, not having passed through a nomomorph stage, while 

 the latter are the degenerate descendants of nomomorphs, or, like the 

 cited Schlotheimia group, the final expression of a nomomorph stock. 

 The African pygmies, the cat and the donkey, are respectively human, 

 feline and equine nannoids : it is for zoologists to say if I read them 

 aright as phaulomorphs and not catamorphs. 



Among Lias Ammonites phaulomorphs are rare — Cheltonia is an 

 instance, Oxynoticeras being the nomomorph. 



Among Inferior Oolite Ammonites phaulomorphs abound, and many 

 are unillustrated. They are usually incipient scaphiticones with fine 

 development of the mouth-border, especially in regard to lateral auricles. 

 The following are a few examples, with their respective nomomorphs : — 



Nomomorphs Phaulomorphs 



Cadotnites Polyplectites 



Lissoceras Cadomoceras 



Slepheoceras, etc. Normannites 



Emileia Otoites 



The theory that the forms now called nomomorphs are the females, 

 and the phaulomorphs the males (Munier-Chalmas, 1892, Haug, 1893), 

 encounters serious objections (r) that various periods lack phaulomorphs, 

 (2) that they are not always found in the same localities as the supposed 

 females, and (3) that there are not enough " husbands " to go round 

 (Buckman & Bather, 1894) ; to which may be added (4) that they do not 

 always occupy the same horizons. 



Among the species now illustrated Coroniceras bucklandi and Goliath- 

 iceras ammonoides are megalomorphs, Docidoceras cylindroides , at present 

 the geologically earliest of the Stepheoceratacea, is a nomomorph : its 

 corresponding phaulomorph is to be figured ; Labyrinthoceras perexpansutn 

 and L. intricatum are colomorphs, but the latter is also, in comparison 

 with the former in its complete state, an incipient catamorph, much on 



