38 NOTES ON AUSTRALIAN CHAETOGNATHA. 
excluding lateral fin, 11.7% of total length ; maximum 
width of fin, 18.2% of total length ; percentage of fin in 
front of tail septum, 3% ; tail, including tail fin, to ventral 
ganglion, 75°% of total length. 
Sp. moretonensis differs from the other two valid 
species of Spadella in the following characters :— 
Sp. schizoptera Conant, possesses two pairs of fins, 
its corona is triangular, its teeth are long and curved, and 
the tail is 51% of the total length. 
Sp. cephaloptera Busch, possesses two rows of teeth, 
the fin begins behind the receptaculum seminis, the corona 
is a long oval and the collarette covers the whole body. 
The possession of a club-like tentacle on each side of the 
head is quoted as one of the distinguishing characters of 
the species. These however do not appear to have been 
seen by subsequent observers, at least some of whom have 
assumed that they had become lost from the specimens 
which they examined. The figures of Sp. cephaloplera, 
which are available to us, and which show the presence of 
these structures, suggest that they are probably not ten- 
tacles but are foreign organisms, probably alge, which 
have accidently developed symmetrically on the head region. 
They remind us of the two club-like bodies present on our 
solitary specimen of Sp. moretonensis. 
The known range of Spadella (sensu stricto) is as 
follows :—Sp. cephaloptera, Atlantic and Mediterranean 
coast of Europe, the Black Sea and the Irish Seas. Sp. 
schizoptera is known only from the Bahamas. Sp. moreton- 
ensis is the first species of the genus to be recorded from the 
Seuthern Hemisphere. 
We take this opportunity to express our thanks to Mr. 
R. L. Higgins for this specimen, which was found among 
alge at Caloundra, July, 1918. 
