M.J. Disney , P.J. Boyce , G.D. Banks, R.F. Minchin , A.E. Wright, PASA, 16 (1), in press.
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Early Results
We have searched the 8 x 4 degree cube by eye, and then again using PICASSO (father of cubism), an automatic galaxy-finding algorithm we have developed at Cardiff (Minchin, 1999). By and large the two searches agree, though not perfectly. As a result we found a total of 102 21-cm sources in the cube (to a flux limit of 1 Jykm 
). This is a conservative lower limit to the number we expect to find eventually and note that the edges of the cube will be noisier due to the survey strategy. Since the number of sources you expect to detect per unit area should go as tobs3/4 this implies a number of detections for the whole sky in HIPASS of 102 x (40,000)/32 x (12.5)-3/4 
20,000. This however is a very rough estimate because of clustering statistics.
Of the 102 sources found, 41 were identified with catalogued galaxies with previously determined redshifts. For most of the remaining 61 sources, there is a catalogued galaxy without a measured redshift lying within 4
of the fitted HI position.
However, there are around a dozen sources for which no such association could be made. Studies of the Digitized Sky Survey fields around these sources revealed possible optical counterparts in most cases. However, there are still 2 for which no counterpart has been identified. Fig. 2 shows the spectrum of one of these objects along with an image of the surrounding DSS field. We are undertaking CCD imaging of these candidate very low surface brightness galaxies.
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