ORDER IV TELOTREMATA Bas: 
chardia, Magas, Magasella, Terebratella, and Magellania. The lower genera become 
adult before reaching the terminal 
stages. Jurato Recent. Recent 
genera restricted to austral seas. 
Bouchardia,Davidson (Pachy- 
rhynchus, King). Recent; South 
Atlantic. 
Magas, Sowerby (Fig. 565). 
Cretaceous; Europe. JJagasella, 
Wall. Recent. Coenothyris, 
Douvillé (Fig. 566). Trias. 
Terebratella, VOrbigny (Del- 
thyris, Menke; Ismenia, King ; 
Waltonia, Davidson), (Fig. 567). 
Jura to Recent. 

Magellania, Bayle (JVald- Fic. 567. PUSHIN: 
eimai <inge: Neothyri : Terebratella dorsata, Magellania flavescens, Val. Recent; 
h AS King ? Neothyi os Dou Lam. sp. Recent ; Australia. Interior of dorsal valve, 
villé), (Fig. 568, also Figs. Chili. 1/;. somewhat enlarged. 
497, 498). Jura to Recent. 
Rhynchorina, Oehlert. Cretaceous. Megerlinu, Deslongchamps. Recent. 
Kraussina, Davidson (Kraussia, Davidson). Recent.  Mannia, Dewalque. 
Miocene. ?Rhynchora, Dalman. Cretaceous. 
Superfamily 3. SPIRIFERACEA. Waagen. 
Telotremata with the adult brachia supported by calcareous spiral lamellae or 
spiralia. Ordovician to Jurassic. 
The Spiriferacea are abundantly represented from the Silurian to the Carboniferous, 
during which time the jugum undergoes many and often rapid changes. The brachidia 
in Zygospira are known to begin with a Centronella-like loop, as in the primitive Tere- 
bratulacec. 
Family 1. Atrypidae. Gill. 
Spiriferacea with the crura directly continuous with the primary lamellae, which 
diverge widely and have the spiral cones between them. 
Jugum simple, complete, or incomplete. Ordovician 
to Devonian. 
This family is divided into Zygospirinae, Dayinae, 
and Atrypinae, according to modifications of the jugum 
or position of the spirals. 
Zygospira, Hall (Anazyga, Davidson ; Orthono- 
maca, Hall; Hallina, Winchell and Schuchert ; 
Protozyga, Hall and Clarke (Fig. 569). Like 
Atrypa, but small, and the spirals composed of 
fewer coils. Jugum a simple connecting band, 

Fig: 569. situated rather anteriorly. Surface sharply 
Zygospira modesta, Hall. Ordovician ; ° 5 , TIALS anc Lae 
Cineinnati, Ohio. .3/; (after Hall). plicate, never lamellose. Ordovician and Sil 
urian ; North America. 
Catazyga, Halland Clarke. More rotund and finely striated than Zygospira, 
