M. 
128 
Krebs! remark: two perfect specimens and two odd 
valves ; perhaps young undatus or decussatus or hirtus ; 
remark: are P. hirtus Phil. and P. undatus L. and P. 
decussatus L. & angulatus L. not synonymes ? 
Heteromyaria. 
Miytilacea. 
Mytilus L. 
exustus L. (M. Domingensis Lmk., dOrb., Hormomya 
Morch) station: on rocks which are over low-water 
mark; habitat: Antillae; Mérch pg. 53! Guadeloupe; 
Beau pg. 22! Rio Janeiro; Cuba; Martinique; dOrb.! 
Jamaica; St. Thomas; Ad.! Virgin-Islands; Swift; Car- 
thagena; St. Thomas; St. Johns; Krebs! remark: it 
evelopes itself very differently in places where the sea is 
smooth and in places where the sea is rough. 
. Lavelleanus d’Orb. station: — ? — ;jhabitat: 
Guadeloupe? d’Orb.! remark: Moll. de Cuba 2—328 
pl. 28 fig. 3—5. 
. Viator d’Orb. station: — ? -- ; habitat: Pata- 
gonia ; Cuba; d’Orb.! 
Modiolus Lmk. 
. americana Tarvart d’Herbigny (M. amer. Leach?, M. 
tulipa Lmk., Perna Adans., Volsella Scop., Pholas KL.) 
station: between seaweed on gravel in a few feet wa- 
ter in creeks; habitat: Antillae; Moérch pg. 53! Gua- 
deloupe; Beau pg. 22! Cuba; Martinique; Guadeloupe; 
St. Lucy; d’Orb.! Jamaica; Bermuda; Ad.! Virgin-Isl. ; 
Swift! all the West-Indian islands from Trinidad to St. 
Domingo; Krebs! 
