Birth may be:  19 Dec 1790, Eisental (Buehl), Baden
Father may be:  Peter STRAUB
Mother may be:  Anna Elisabeth BAUER

Birth may be:  13 Feb 1822, Muellenbach, Rhineland-Palatinate
Father may be:  Sebastian STOLZ
Mother may be:  Justine SENN

1.  LDS.  Family Search: Internet Genealogy Service: IGI - International Genealogical Index (online at FamilySearch.org).

This is doubtfully our subject because he's very old for having a first marriage in 1844, but if so, he presumably had a wife prior to Apollonia and even prior to Mathilde:

Lazarus STRAUB Birth: 19 Dec 1790, Eisental, Baden, Baden Father: Peter STRAUB; Mother: Anna Elisabeth BAUER Source: patron submission

This may be our subject's prior wife:

Mechtilde KLOPFER Birth: 29 Mar 1819 Christening: 29 Mar 1819, Gottmadingen, Konstanz, Baden Father: Theodorus KLOPFER; Mother: Maria MARGRAF Source: patron submission

This may be our subject's prior marriage:

Lazarus STRAUB Spouse: Mathilde KLOEPFER Marriage: 26 Jul 1837, Katholisch, Eisental, Baden, Baden Source: Kirchenbuch, 1810-1900. Katholische Kirche Eisental (A. Baden)

This may be our subject's wife:

Apollonie STOLZ Birth: 13 Feb 1822, Muellenbach Christening: 13 Feb 1822, Germany, Eisental, Baden, Baden Father: Sebastian STOLZ; Mother: Justine SENN Source: Kirchenbuch, 1810-1900. Katholische Kirche Eisental (A. Baden)

This does appear to be our subject's marriage:

Lazarus STRAUB Spouse: Apollonia STOLZ Marriage: 08 May 1844, Katholisch, Eisental, Baden, Baden Source: Kirchenbuch, 1810-1900. Katholische Kirche Eisental (A. Baden)

These do appear to be our subject's children:

Maria Josepha STRAUB Birth: 21 Aug 1845, Katholisch, Eisental, Baden, Baden Christening: 21 Aug 1845, Germany, Eisental, Baden, Baden Death: 19 Dec 1845 Father: Lazarus STRAUB; Mother: Apollonia STOLZ Source: Kirchenbuch, 1810-1900. Katholische Kirche Eisental (A. Baden)

Maria Josepha STRAUB Birth: 27 Sep 1846, Katholisch, Eisental, Baden, Baden Christening: 28 Sep 1846, Germany, Eisental, Baden, Baden Father: Lazarus STRAUB; Mother: Apollonia STOLZ Source: Kirchenbuch, 1810-1900. Katholische Kirche Eisental (A. Baden)

Karolina STRAUB Birth: 08 Feb 1852, Katholisch, Eisental, Baden, Baden Christening: 10 Feb 1852, Germany, Eisental, Baden, Baden Father: Lazarus STRAUB; Mother: Apollonia STOLZ Source: Kirchenbuch, 1810-1900. Katholische Kirche Eisental (A. Baden)

2.  Archives of the STRAUB Mailing List (online at RootsWeb.com).