100 Moll . 
MOLLUSCA. 
Anodonta calif orniensis (Lea), varieties from several rivers in Cali- 
fornia and Utah ; Stearns, Am. Nat. xiii. pp, 145, 149, 151, woodcuts. 
Anodonta pastasana (Clessin), sp. n.. Miller, Mai. Bl. (2) i. p. 173, 
pi. xi. fig. 1, Rio Pastasa, Ecuador. 
Mycetopus occidentalia (Clessin), sp. n., id. 1. c. p. 174, pi. xi. figs. 2 & 3, 
Rio Pastasa. 
Dreysstnid^e. 
Praxis miller i and ecuadoriana (Clessin), spp. nn., Miller, 1. c. 
pp. 179-181, pi. XV. figs. 7 & 8, Prov. Esmeraldas, Ecuador. 
Mylilus incurvatiis (Philippi, as Modiola) = Modiola martorellii (Hid- 
algo), found living in the Mediterranean during the ‘ Porcupine * Expe- 
tion ; byssus very long. Jeffreys, P. Z. S. 1879, p. 566. 
Modiola modiolus (L.). The byssus is composed of longitudinal bands ; 
young animal with expansions of the mantle which cause the horny 
bristles on the outside of the shell ; Bouchard-Chantereaux, J. de Conch, 
xxvii. pp. 123 & 124. 
Lithodomus bipenniferus, sp. n., Guppy, P. Sc. Assoc. Trinidad, xi. [Dec., 
1877] p. 154, Gulf of Paria. 
[Crenella'] Modiola discors (L.). Structure of gills ; see above in the 
General Subject. 
Crenella australis^ sp. n.. Martens, MB. Ak. Berl. 1879, p. 742, Inham- 
bane, coast of Mozambique. 
Dacrydium vitreum (Holboll, Moller) = Modiola pygmcea (Philippi) = 
D. hyalinum (Monterosato), found in the North Atlantic during the 
‘ Porcupine ’ Expedition ; it makes a nest, like Modiolaria discors and 
Lima Mans. Jeffreys, 1. c. p. 569. 
Aviculid^. 
Avicula. W. Dunker continues his monograph [Zool. Rec, ix. p. 172] 
describing and figuring 25 more species, for the most part copied from 
Reeve. A. jamaicensis^ new name for cornea (Reeve), preoccupied, p. 65 ; 
A .japonica, coturnix^ loveni^ spp. nn., J apan, versicolor and undata^ spp. nn.,- 
locality unknown, pp. 66-68, pi. xxiii. figs. 2-6, pi. xxiv. figs. 1-6. 
Avicula fusco-purpurea (E. A. Smith, 1876) ; E. A. Smith, Phil. Tr. 
clxviii. p. 483, pi. li. fig. 5, Rodriguez Island [probably = A. ala-corvi, 
Chemn.] 
Vulsella spongiarum (Lam.). Note on young specimens ; Troschel, 
MB. Ak. Berl. 1879, p. 760. 
Pinna muricaia (L., Reeve), var. p, from Rodriguez ; E. A. Smith, 1. c. 
p. 479. 
Arcid.®. 
Area frielii (Jeffreys & Friele, 1877), Novaya Zemlya, figured by 
Jeffreys from specimens found during the ‘ Porcupine ’ Expedition ; 
