BRACHIOPODA. 



77 



The sexes are usually separate. The reproductive cells are 

 formed in the body-cavity. The embryo swims freely for a short 



Fig. 3. 



Magellania Jlavescens. (After Davidson.) 



A. Interior of dorsal valve to show the " arms" ; some of cirri removed on right 



side ; v, mouth. B. Longitudinal section, with a portion of the animal. 



time before settling down and becoming fixed. The specimens 

 exhibited in the case are arranged according to the following 

 classification : — ■ 



I Order 1. Atremata. Fam. Lingulidse. 



„,„--., . (■ Fam. Discinidx. 



Order 2. Neotremata. < t, ^ . . , 

 \ Fam. Crumidce. 



( Order 3. Protremata. Fam. Thecidiidse. 



Section II. Akticulata. 



(Fam. Jihynchonellidee. 

 Fam. Terehratulidx. 

 Fam. Terehratellidst. 



Section I. — Inaeticulata. 



Order 1. — Atremata. Family LinguUdce. — The Lingulas possess 

 emerald green or golden brown duck-bill-shaped shells. Having no 



