THE BRITISH PYCNOGONOIDBA. 199 
Phoxichilidium (M. Edwards) Phowichilidium virescens, Hodge 
coecineum, Johnston, Pasithoe (Goodsir) 
globosum, Goodsir, vesiculosa, Goodsir 
olivaceum, Gosse. Phoxichilus (Latreille) 
petiolatum, Kroyer spinosus, Montagu. 
ot Pycnogonum (Fabricius) 
littorale, Strom. 
There can be little doubt that a careful examination of the 
species found on various parts of our coast would add many 
new forms to this list, especially amongst the smaller species. 
Whilst most departments of Marine Zoology have made rapid 
strides within the last few years, our knowledge of the Pycnogons 
has scarcely advanced: no doubt this is owing, In a great 
measure, to the difficulty of determining the species in conse- 
quence of there being no complete list. It is hoped the fore- 
going may in some degree supply this want, and lead to these 
animals being better known and understood. 
EXPLANATION OF PLATES IV, & V. 
Fig 1 Ammothoa brevipes. 
2 i foot-jaws, 
3 7 tarsus, &¢, 
4 a side view. 
5 Ammothoa longipes. 
6 fe tarsus, &c. 
7 Achelia echinata. 
8 ‘i side view. 
9 5 rostrum, palpi and oculiferous tubercle, 
10 Ss tip of false foot of female. 
11 Achelia hispida. 
12 Achelia levis. 
13 Phoxichilidium virescens. 
14 EY foot-jaws. 
15 3 tarsus, &c. 
16 Pallene pygmza. 
17 3 tarsus, &c, 
