OFFER OF CONTINUED EMPLOYMENT

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                                                                   EXHIBIT 10.67


September 7, 2005


Mr. David Manyak, Ph.D.
[address]

Dear David,

I am pleased to offer you continued employment with NovaScreen Biosciences
Corporation ("NovaScreen") upon the closing of the acquisition of NovaScreen by
Caliper Life Sciences, Inc. ("Caliper") (the "Closing"). After the Closing,
Caliper agrees that you will continue in your position as President of
NovaScreen and that you will be the "Surviving Corporation President" under the
terms of and as that term is defined in the Agreement and Plan of Merger entered
into by and among NovaScreen, Caliper and Caliper Services, Inc. (the "Merger
Agreement"). In addition, subject to approval by Caliper's Board of Directors,
you will serve Caliper as Executive Vice President, Drug Discovery Services,
reporting directly to me. We look forward to you applying your leadership skills
as a member of NovaScreen's and Caliper's Executive Teams. The offer embodied by
this offer letter is irrevocable so long as the Merger Agreement remains in
effect, but notwithstanding your prior acceptance of this offer letter, the
commencement of your employment with Caliper and NovaScreen as the surviving
corporation in the merger, and the effectiveness of this letter agreement, is
contingent upon the occurrence of the Closing under the Merger Agreement. The
offer embodied hereby, and any acceptance on your part , shall in any event be
null and void and have no force or effect upon the termination for any reason of
the Merger Agreement without the occurrence of a Closing thereunder.

To compensate you for your continued efforts in this position, you will receive
a compensation package, including base salary, target bonus and benefits, as set
forth in this offer letter.

Your base salary will be $9,916.67 per semi-monthly payroll (equivalent to
$238,000 per annum), with a target annual bonus of 45% of your aggregate salary
paid during any calendar year. Your actual bonus will be based on Caliper's
performance against corporate goals determined by Caliper's Board of Directors
and your individual performance, all in accordance with the terms of Caliper's
Performance Bonus Plan. Your annual bonus for 2005 will be pro-rated based on
the time period from the Closing to the end of the calendar year. Your actual
bonus is calculated by multiplying the bonus opportunity times the corporate
achievement factor times your individual performance factor. For the 2005 annual
bonus, the corporate achievement factor used to determine your bonus shall be
one (1) and the individual performance factor will be no less than seven-tenths
(.7). However, if the 2005 Milestone (as defined in the Merger Agreement) is
achieved, then the aggregate corporate and personal bonus factor for your 2005
annual bonus shall be no less than 1.4. You must be employed with NovaScreen on
the date that the bonus is paid in order to be eligible for the bonus. All
stated compensation is subject to standard payroll deductions and withholdings.

In addition, I will be recommending to Caliper's Board of Directors that you be
granted a Caliper common stock equity award pursuant to Caliper's 1999 Equity
Incentive Plan (the "Plan") in the form and amount of (i) an option to purchase
20,000 shares of common stock of Caliper, and (ii) 20,000 restricted stock units
of Caliper. Subject to obtaining Caliper's Board's approval, it is our intent
that the effective date of these grants will be the date of the Closing, and the
exercise price


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per share for the stock option will be the closing sale price of Caliper common
stock as