EEPORT ON THE ANNELIDA. 
139 
downward superiorly. This probably indicates the special fold in certain of the 
Sigalionidse. The space between these muscles is considerably less than in the 
Polynoidse. The dorsal longitudinal muscles are simple and almost connate superiorly. 
The proboscis seems to approach that of the Polynoidse in general structure. 
The genus Eupompe established by Kinberg in 1855^ for the reception of an 
example of the Acoetidse from the vicinity of Guayaquil, Ecuador, South America. 
From this species that dredged by the Challenger is separated by the form of the 
cephalic processes and cirri, the presence of the pair of sessile eyes behind the ommato- 
phores, and the structure of the bristles. None of the brush-sbaped bristles,^ moreover, 
seem to occur in this species. 
Family Sigalionida:. 
The examples of this family are twelve in number, three ranging themselves under 
Thalenessa, one under Sigalion, two under Psammolyce, five under Leanira, and one 
under Eupholoe. 
The genus Thalenessa was established by Dr. Baird in 1865 for Sigalion edwardsi, 
Kinberg, but as it appears to be unnecessary to constitute a genus for a form that readily 
falls under Sigalion, it has been selected for the present group, all of which are new. 
All the species included in the genus Psammolyce are likewise novel, and four of the 
five species falling under Leanira are new. A distinct genus also requires to be con- 
stituted for the novel type Eupholoe philippensis, a form apparently intermediate 
between Psammolyce and Pholoe. 
The collection made by the Challenger compares favourably with those made by 
other expeditions. Thus, for example, nine are given by Kinberg, one by Schmarda, 
four by Grube in his Philippine Annelids, and five in his list of Annelids from the 
“ Gazelle.” 
The species range from shallow water (5 fathoms and under) to 1000 fathoms, the 
same genus {Leanira) in the present instance occurring at each extremity. 
Thalenessa, Baird, char, emend. 
Head with four large eyes, a very short tentacle, and a pair of antennae. Scales 
leaving the dorsum uncovered anteriorly, and furnished with ramose papillae on the 
margin. The feet present lamellar processes at the tip, and the ventral bristles are 
much stronger than in either Sthenelais or Sigalion. The ventral cirrus is also longer. 
It approaches Leanira in the structure of the head. 
^ Ofversigt Ic. Vetensk.-Akad. FbrJiandl., 1855, p. .386. 
^ Freg. Engen. Eesa, Taf. vii. fig. 35, Gs. 
