Why are the Psalms numbered this way in some Catholic Bibles? I am looking at a Catholic Bible and I see the following:


PSALM 1
[...]
PSALM 9-10
[...]
PSALM 51 V50 Miserere
PSLAM 52 V 51
[...]
PSALM 150


Please see image below.

What accounts for this numbering?  

It is not a straight 1 thru 150 numbering. For example there is Psalm 9-10 and Psalm 51 has V50 alongside it.

I am looking for a Catholic explanation sought but I assume a Bible scholar ought to be able to explain it.



Image produced from The Jerusalem Bible Popular Edition.
There is a difference in numbering between the Hebrew (Masoretic) text and the Greek and Latin (Septuagint and Vulgate). Psalms 9 and 10 in the Hebrew get combined into one as do Ps 114 &amp; 115. Psalms 116 and 147 both get split in two.

Most Protestant Bibles follow the Hebrew numbering while most Catholic and Orthodox ones follow the Greek. 

I suspect the reason for the difference is that the numbers were added to the Hebrew and Greek manuscripts at a later date and there were different opinions as to where one finished and the next began.  




Cf. Septuagint (LXX) numbering of the Psalms | The Orthodox Church in America.
Cf. Note on the different numbering of the 150 Psalms | psalmen.wursten.be.