It's unclear what you're asking. It seems you want the numbers to become elements of the array, but what about James? Are there any other names in your input?

Maybe you rather need a hash of arrays, HoA, using the names as the keys and arrays of numbers as values?

#!/usr/bin/perl
use warnings;
use strict;

my %hash;
my $name;
while (<DATA>) {
    chomp;
    if ($. % 2) {  # Even lines.
        $name = $_;
    } else {
        push @{ $hash{$name} }, $_;
    }
}

use Data::Dumper;
print Dumper \%hash;

__DATA__
James
40
Philip
12
James
35
James
26
James
15
Philip
27
[download]

Output:

$VAR1 = {
          'James' => [
                       '40',
                       '35',
                       '26',
                       '15'
                     ],
          'Philip' => [
                        '12',
                        '27'
                      ]
        };
[download]