Javascript function not showing second form name

I have 2 forms with different ids, in javasciprt function i m going to get form id in variable name, but in name variable only first forms id is going, not going form 2 id my code is. HTML CODE:

<form name="form" id="filterMemberByFamNum" class="form-horizontal" role="form">
        <div class="form-group">
            <label>Family Number</label> <input type="text" name="familyNumber" placeholder="Family Number" class="form-control">
        </div>
        <button type="button" class="btn btn-primary" onclick="filterMembers();return false;">Submit</button>
</form>
<form name="form" id="filterMemberByMemName" class="form-horizontal" role="form">
    <div class="form-group">
        <label>Member Name</label> <input type="text" name="member" placeholder="Member Name" class="form-control">
    </div>
    <button type="button" class="btn btn-primary" onclick="filterMembers();return false;">Submit</button>
</form>

and JS is

function filterMembers(){
    //alert("Submitted");
    var str = $("form").serialize();
    var name = $(this.form).attr('id');
    console.log(name);
    $.post("model/handler.php?name="+name+"&op=formSubmit",
        {
            'data':str
        },function(data){
            $('#members').html(data);
        },"json");
    return false;
}

Any time output result in console tab is "filterMemberByFamNum" infact i m submitting "filterMemberByMemName" form. Please help me.