450 SPECIES OF THE SYSTEMA. 
seems to disturb this conclusion, yet, although that species 
might answer to the description, it possesses not the additional 
characters gleaned from the cited engravings. The reference 
to the earlier edition of Lister's ‘ Historie’ has been changed 
to “548, f. 3,” by our author, who has likewise quoted the 
“Act. Nidros. vol. iv. pl. 4, f. 9, 10,’ where the fragment 
alluded to is most admirably depicted. 
TEREDO. 
Teredo navalis. 
It is impossible to determine, from the language of Linneus, 
to what particular species of ship-worm the very comprehensive 
term navalis should be restricted. The original account in the 
tenth edition of the ‘Systema’ (p. 651), where it was doubtfully 
placed with the intestinal worms, is much more elaborate and 
full of detail than in the final edition, and the “angulo recto et 
obtuso” of the valves assuredly limits in some measure the 
number of species to which the description might otherwise 
be applied. Our author has not indicated his possession of 
examples, consequently his cabinet affords no assistance in the 
investigation. Four works are referred to for the synonymy : 
Plancus, whose expressions are applicable to any ship-worm ; 
Vallisnieri, whose figure, from the neglect of sculpture, is irre- 
cognisable; the ‘Fauna Suecica;’ and the Monograph of 
Sellius. This last reference is highly important, not merely 
on account of the merits of the engraving, where both valves 
and pallets are clearly delineated, but because it was the only 
illustration quoted in the ‘Fauna Suecica.’ The 7’. navalis of 
that work, then, is a pictorially defined, determinable species, 
and is identical, as Lovén has remarked, with the 7. Batava of 
Spengler. It is not the navalis of the earlier British writers, 
