The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
Estimated average burden
hours per response: 23.8
COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
BARCLAYS BK PLC CONV ZERO CPN Convertible Bonds 06741JV89 42 46,000 PRN   SOLE 0 46,000 0 0
LAYNE CHRISTENSEN 4.25 CONVERT DUE 11/15/2018 Convertible Bonds 521050AB0 10,644 10,952,000 PRN   SOLE 0 10,952,000 0 0
APPLE INC. Common Stocks 037833100 25,778 152,324 SH   SOLE 0 152,324 0 0
ABB LIMITED Common Stocks 000375204 10,625 396,167 SH   SOLE 0 396,167 0 0
ACCENTURE PLC Common Stocks G1151C101 7,426 48,508 SH   SOLE 0 48,508 0 0
AMGEN INC Common Stocks 031162100 261 1,500 SH   SOLE 0 1,500 0 0
BRISTOL-MYERS SQUIBB CO Common Stocks 110122108 8,293 135,332 SH   SOLE 0 135,332 0 0
CELGENE CORPORATION Common Stocks 151020104 17,692 169,526 SH   SOLE 0 169,526 0 0
CHECK POINT SOFTWARE TECH Common Stocks M22465104 11,119 107,304 SH   SOLE 0 107,304 0 0
CISCO SYSTEMS, INC. Common Stocks 17275R102 214 5,600 SH   SOLE 0 5,600 0 0
CHEVRON CORP. Common Stocks 166764100 207 1,650 SH   SOLE 0 1,650 0 0
DISH NETWORK CORP Common Stocks 25470M109 529 11,075 SH   SOLE 0 11,075 0 0
DORCHESTER MINERALS LP Common Stocks 25820R105 929 61,130 SH   SOLE 0 61,130 0 0
DELL TECHNOLOGIES CLASS V Common Stocks 24703L103 15,941 196,121 SH   SOLE 0 196,121 0 0
ENTERPRISE PRODUCTS PRTNS Common Stocks 293792107 27,966 1,054,928 SH   SOLE 0 1,054,928 0 0
TWENTY-FIRST CENTURY FOX, INC Common Stocks 90130A101 10,795 312,634 SH   SOLE 0 312,634 0 0
GILEAD SCIENCES, INC Common Stocks 375558103 12,004 167,555 SH   SOLE 0 167,555 0 0
ALPHABET INC CL C (GOOGLE C) Common Stocks 02079K107 29,971 28,642 SH   SOLE 0 28,642 0 0
ALPHABET INC CL A (GOOGLE A) Common Stocks 02079K305 18,467 17,531 SH   SOLE 0 17,531 0 0
HONEYWELL INTL INC Common Stocks 438516106 2,196 14,321 SH   SOLE 0 14,321 0 0
INDEPENDENT BANK GROUP, INC Common Stocks 45384B106 474 7,014 SH   SOLE 0 7,014 0 0
INOVALON HOLDINGS INC. (Class A) Common Stocks 45781D101 11,696 779,735 SH   SOLE 0 779,735 0 0
KINDER MORGAN, INC. Common Stocks 49456B101 17,668 977,738 SH   SOLE 0 977,738 0 0
LAS VEGAS SANDS Common Stocks 517834107 12,290 176,867 SH   SOLE 0 176,867 0 0
MONSANTO COMPANY Common Stocks 61166W101 20,639 176,733 SH   SOLE 0 176,733 0 0
THE MOSAIC COMPANY Common Stocks 61945C103 5,077 197,839 SH   SOLE 0 197,839 0 0
MATADOR RESOURCES CO. Common Stocks 576485205 1,401 45,000 SH   SOLE 0 45,000 0 0
NOBLE ENERGY INC Common Stocks 655044105 8,332 285,918 SH   SOLE 0 285,918 0 0
QUALCOMM INC Common Stocks 747525103 30,288 473,096 SH   SOLE 0 473,096 0 0
SCHLUMBERGER LTD Common Stocks 806857108 11,115 164,934 SH   SOLE 0 164,934 0 0
XYLEM INC. Common Stocks 98419M100 11,273 165,286 SH   SOLE 0 165,286 0 0