254 GINGLYMACONCHA. PHOLADID. 
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Genus 4. Capmusia. Tab. M4T- figs. 1, 2. 
The shells short, equivalve: that part of the epidermis 
covering the respiratory tubes is testaceous; the accessory 
valves two, unequal, post-umbonic, delineating an angle. The 
tracheal tubes short. The foot short and obtuse. 
XI 
Capmusia SOLANDERIA. Tab. MH fies. ly 2. 
The shell anteriorly smooth, with elevated, narrow, rather 
rough strize ; the epidermis iridescent anteriorly below, behind 
and on the respiratory tubes fulvous olive. 
Pholas papyraceus, Solander, MSS. 
Var. a. The strize of the anterior part of the shell undulated ; 
the oblique line simple. 
Var. 3. The strie of the anterior part of the shell simple ; the 
oblique line wrinkled (fig. 2). 
Inhabits the western coasts of Devon, perforating rocks. 
Having in the collection which I have presented to the 
British Museum a complete series, from the youngest specimens 
to the adult ones, and having likewise a complete series of all 
the varieties of this species, I am confident that no one who 
will take the trouble of examining this series but will agree 
with me in considering them as mere varieties, forming but 
one species. 
I have placed in the British Museum some exotic species, 
forming two or three genera, having that part of the epidermis 
which covers their respiratory tubes shelly, as in this British 
species. 
I have named this species in honour of Dr. Solander; and 
should not have changed its name, had it not been equally 
applicable to species of other genera: his collection is in the 
Museum of the Linnzan Society. 
Genus 5. BARNIA. 
Shell oblong (the left valve a little longer than the right 
valve), anteriorly entire and closed, gaping behind ; the reflected 
part hollow beneath and simple. Hinge in each valve with an 
