110 
PACIFIC SCIENCE, Voi XIV, April I960 
A total of 463 specimens, of which 300 oc- 
curred at Station 826, were collected from eight 
stations between Cook Strait (January, 1951) 
and the subantarctic. 
Figures 14 and 15 illustrate the chief features 
of the species. In the solitary form (Fig. 14) 
the test is flaccid anteriorly, more rigid pos- 
teriorly and with several short projections. Body 
muscles I— III and VIII-IX are in contact dor- 
sally, the remainder are parallel. In the aggre- 
gate form (Fig. 15) the test is more or less 
rigid, with elongate anterior and posterior proc- 
esses. Body muscles I-IV are in contact dorsally, 
and IV-V laterally. 
The f. asp era is distinguished from fusiformis 
s. sir . by the ridged and spinose character of the 
test and processes, although on some specimens 
it is inconspicuous, and they could readily be 
mistaken for smooth forms. 
Only specimens of f. asp era were collected 
by the "Lachlan.” 
FIGS. 14, 15. Salpa fusiformis f. as per a, solitary and 
aggregate forms. 
FIGS. 16, 17. Ihlea magalhanica, solitary and aggre- 
gate forms. 
Genus Ihlea Metcalf 
Ihlea magalhanica Apstein 
Ihlea magalhanica Thompson, 1948 
Specimens were common in the shallow 
waters of Foveaux Strait and northward to 
Dunedin; a few occurred at Station 326, south 
of Cook Strait. 
The test is flaccid in both forms. The solitary 
form (Fig. 16) has a stout, conical process 
posteriorly on the test. There are seven body 
muscles. M.I-MiV touch, but do not fuse, dor- 
sally and ventrally; M.IV and V touch laterally 
and V and VI dorsally. The test of the aggregate 
form (Fig. 17) has a short anterior and longer 
posterior process, and the body Is decidedly 
asymmetrical. There are five body muscles. 
M.I-III touch dorsally and Mill and IV almost 
touch dorsolaterally; Mil and III, III and IV, 
IV and V are connected medioventrally by anas- 
tomoses; M.V is incomplete ventrally. 
DISTRIBUTION AND ECOLOGY OF SPECIES 
Oikoplema fusiformis 
Oikopleura fusiformis is usually described as 
inhabiting warm, oceanic waters, although ac- 
cording to Thompson (1948), Lohmann ob- 
tained it in Plankton-Expedition samples from 
waters of 3 to 37.4 0 / 0 o salinity, and tem- 
peratures of 9-3° to 29-5° C. The salinity range 
of Lachlan material (Fig. 22) is 34.15 to 
34.63 °/oo* The lowest temperature at which 
