OCCASIONAL PAPERS OF THE CALIFORNIA ACADEMY OF SCIENCES No. 86, ^37 pages, Frontispiece, 21 figures. THE SEFTON FOUNDATION ORCA EXPEDITION TO THE GULF OF CALIFORNIA, MARCH-APRIL, 195 3. GENERAL ACCOUNT By Paul H. Arnaud, Jr. California Academy of Sciences, San Francisco 94118 SAN FRANCISCO PUBLISHED BY THE ACADEMY September 18, 1970 Marine Biological Laboraov I_l BRA - OCT 2 7 1970 WOODS HOLE, :.;A.^. FRONTISPIECE. Mr. Joseph W. Sefton, Jr. Born on September 4, 1882, at Dayton, Ohio. Died on March 3, 1966, at San Diego, California. To whom this report is respect- fully dedicated. (Photograph taken by Dr. G. E. Lindsay.) OCCASIONAL PAPERS OF THE CALIFORNIA ACADEMY OF SCIENCES No. 86, 37 pages, Frontispiece, 21 figures. THE SEFTON FOUNDATION ORCA EXPEDITION TO THE GULF OF CALIFORNIA, MARCH-APRIL, 195 3. GENERAL ACCOUNT By Paul H. Arnaud, Jr. California Academy of Sciences, San Francisco 94118 INTRODUCTION The 1953 Sefton Foundation Ovoa Expedition was a sea voyage for the biological investigation of the waters and the islands of the Gulf of California and the adjacent shores of Baja California and Sonora. Emphasis was placed on the collection of arachnids, fishes, insects (primarily Diptera) , mollusks (recent and fossil), and reptiles, with the objective of studying the effects of insular isolation on the populations of the land forms and of comparing the present and past distribution of the marine invertebrate faunas . The Gulf of California (Golfo de California) or Sea of Cortez (Mar de Cortez) , is an elongate body of water some 650 miles in length and from 50 to 150 miles in width, dot- ted primarily on its western side and to a lesser degree elsewhere with islands which vary considerably in size. This is an almost unique living biological laboratory which is infrequently duplicated in other parts of the world. The expedition v;as sponsored by the J. W. Sefton Founda- tion of San Diego, California, which furnished its research ship Ovoa, a twin-screw steel-hulled motor ship, 98 feet overall, with 23 foot beam (fig. 1) especially fitted for biological research. In addition to a large laboratory, its equipment included a heavy dredging winch, dredges, and various marine collecting gear. It was also equipped with two motor launches and various smaller boats. The Ovoa is now operated by the Scripps Institution of Oceanography, La Jolla, California. The 1953 Sefton Foundation Ovoa Expedition to the Gulf of California was the second expedition to the Gulf of California to be sponsored by the Sefton Foundation. The first, in 1952, under the leadership of George E. Lindsay 2 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers (1952: 1-98), sailed from San Diego, California, on March 26, 1952, and was out 61 days. Mr. Sefton was unable to accompany the Ovoa in 1952, but in 1953 he accompanied the expedition and took an active and enthusiastic part, aiding in the collecting activities whenever possible. The officers of the Ovca, Captain Stanley Ellis, Engi- neer James McNeilage, and crewman Joe Wall, were most capa- ble and aided in all ways to attain the expedition's objec- tives. Mr. Webster Jackson, Mr. Sefton' s personal cook, provided excellent meals to the personnel of the expedi- tion. The scientific personnel also served as crew members whenever necessary. Three groups of biologists utilized the research ship Orca in the Gulf of California in 1953. This report in- tends to cover the exploration of two portions of the trip, the first from March 9 through April 5, 1953, and the sec- ond from April 6 through 15, 1953. Exploration undertaken subsequently into May by members of the University of Cali- fornia, Los Angeles, is not considered in this report. The scientific personnel (with their fields of interest indicated within parentheses) for the first portion (March 9 - April 5) of the trip consisted of: from the California Academy of Sciences, Dr. G Dallas Hanna (paleontology, conchology) and Mr. Joseph R. Slevin (herpetology) ; from Stanford University, the then graduate students in biology, Paul H. Arnaud, Jr. (entomology) , John C. Briggs (ichthyol- ogy) , Frank S. Cliff (herpetology) , John P. Figg-Hoblyn (Coleoptera, herpetology) , Bruce L. Firstman (arachnology) , and Alan E. Levi ton (herpetology) ; and from the San Diego Zoological Society, Mr. Joseph Ball (herpetology) . It was a pleasure for the younger biologists to have Dr. Hanna and Mr. Slevin, both experieneed field zoologists, as associ- ates on this expedition. Mr. Slevin, 32 years earlier, had been in charge of the 87 day California Academy of Sciences' 1921 expedition to the Gulf of California (Slevin, 1923: 55-72), aboard the Silver Gate. In the following year, 1922, Dr. Hanna (1925: 217-275) had explored the Island of Guadalupe and other Pacific islands on the Teaate. The scientific personnel for the second portion (April 6-17) of the trip consisted of Dr. Hanna and Mr. Slevin who continued on the expedition, and Dr. Rolf F. Bolin of Hop- kins Marine Station (ichthyology) . Two San Diego residents were also aboard. ACKNOWLEDGMENTS The J. W. Sefton Foundation of San Diego, California, provided the research ship Ovoa, its crew, as well as fuel and food. To the late Mr. J. W. Sefton, Jr. (frontispiece) , formerly President, San Diego Trust and Savings Bank, must be acknowledged our gratitude for his establishing the Sef- ton Foundation, and for the rebuilding of the ship Ovoa for the specific purpose of advancing biological research, thereby making this expedition possible. This report is dedicated to Mr. Sefton, but this can only express a small token of our thanks. Dr. George E. Lindsay made all the No. 86] ARNAUD: ORCA EXPEDITION 3 advance arrangements , even though he could not accompany the expedition, and he also invited the participants. Dr. G Dallas Hanna and Mr. J. R. Slevin kindly made their field notes available, which permitted this report to be written. Dr. Hanna originally planned, in cooperation with Mr. Slevin, to prepare a general account of this expedition, but preoccupation with other research prevented his under- taking this project. Credit for all information of geolog- ical, conchological, and other invertebrate coverage (other than insects which are those of the writer) should be given to Dr. Hanna. Dr. Laurence Binford, Mrs. Lilian Dempster, Dr. William Eschmeyer, Dr. Leo G. Hertlein, Dr. Elizabeth McClintock and Mr. Allyn G. Smith of the California Academy of Sciences kindly confirmed some of the scientific names. Finally, thanks are extended to all members of the scien- tific party and crew for their cooperation and dedication in making this expedition a success. LOG OF THE TRIP Part I. March 9 - April 5, 1953 March 9, 195 3. Monday. San Diego, California to Cabo Col- nett, Baja California Norte. We left the dock at San Diego at 0600. A low thin fog was present until mid-afternoon when it lifted. A fair wind and gentle following sea were with us. We dropped an- chor under the lee of Cabo Colnett for the night at 1800. From the ship, in dim light, the cape seemed to be a mass of yellow, horizontal, poorly bedded, hard, and concretion- ary sandstone about 100 feet thick, capped with a volcanic flow rock about 50 feet thick at the point and thinning to the east and north. We anchored opposite a gully which would afford access to the water line. Otherwise the cliffs are vertical. No shore collecting was undertaken. A night light hung over ship side attracted larval fishes (probably anchovies) and many reddish wo inns . Other forms were less abundant. Many fish were seen swimming at depth but could not be captured. A good series of pipe fish, a small slender species, was taken. The depth of water at anchorage was three fathoms. Temperature about 58° F. from 1900 to 2100. March 10, 1953. Tuesday. Cabo Colnett, Baja California Norte to Is la San Geronimo. We left Cabo Colnett anchorage at 0600 with fine weather and sunrise, and a light fair wind and small following sea. We passed close to Isla San Martin at 1000 to 1100 hours and it looked enticing for a collector. Very little sea life was seen on the way. At 140 0 we arrived and made an- chorage under the lee of Isla San Geronimo. On this small island, which is about 100 feet high, we found a Mexican colony of lobster fishermen with their families, and their domesticated pigs and chickens. We did not know the number of residents of the colony, but they had 31 skiffs and a launch on the beach. All collectors went ashore on the 4 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers south end of the island. The north end, a refuge inhabited by many cormorants, is forbidden to trespassers because of a guano concession. Two species of lizards were taken. Large series of seashore Diptera -- Canaoeoides nudatus and Aphrosytus — as well as other insects and spiders, were collected. Hanna collected a few representative rocks and shells. Mollusks seen were the usual ones found from Santa Barbara to San Diego. The tide was high. The island is primarily a mass of yellow sandstone dipping northwest 10 to 20 degrees, somewhat cross bedded. No traces of fossils could be found except a little wood. Some strata are some- what shaly with limey concretions but these have no fossils. Beaches are composed of pebbles of very dark meta volcan- ics and very hard igneous rocks. An irregular layer of these covers much of the surface of the south half of the island. Immediately below this layer the contact is marked by highly bored sandstone, showing clearly that the island has been elevated from the sea bottom. No land shells were found. There were many burrows of Cassin's Auklets [Pty- ahoramphus aleutioa) with eggs. No fish were caught on the hooks at the ship. March 11, 1953. Wednesday. Isla San Geronimo to Bahia del Sur, Isla de Cedros. We left anchorage at 0600 under clear skies. There were moderate swells with a brisk wind of 20 miles from the northwest. Near San Geronimo were sighted about 100 cor- morants with white flank patches -- the pelagic cormorant {Phalaovooorax pelagious) . By mid-afternoon Isla de Cedros and the Islas San Benito came in sight. Two trolling hooks failed to catch anything, and there was little life in sight. We passed on the western side of Isla de Cedros and dropped anchor at 1730 in its Bahia del Sur (South Bay) . There was a heavy ground swell. The air and water were cold and the wind did not slacken. The entire southwest corner of Cedros seemed to be volcanic, judging by the red cinder cones seen from the ship. On the west side, a few miles north, there is a flat-topped area which looked like a terrace about 100 feet high but the remainder of the shore line is not like this. No shore collecting was un- dertaken. We tried hook and line at the anchorage with various baits including live smelt but did not have a strike. At the night light many five-inch smelt came in and these were netted for bait. One large pipe fish which was dark brown dorsally with ten light yellowish brown cross bars was caught. Red worms swarmed about the light. March 12, 1953. Thursday. Bahia del Sur, Isla de Cedros to Bahia San Bartolome, Baja California Sur. In the morning a landing party consisting of Levi ton, Firstman, Figg-Hoblyn, Ball, and Arnaud tried to row ashore, The surf was so high that the large skiff was overturned, bow over stern. No one was injured, but all got coldly soaked and some equipment was lost — including two 22 cal- iber rifles, cameras, boots, and other clothing. No col- lecting was attempted. After this the party returned to the Orca. We sailed at 1030 and passed to the north of No. 86] ARNAUD: ORCA EXPEDITION 5 Isla Natividad where there is a lighthouse and what appears to be a weather station. Several large giant cacti {Paohy- aereus pringZei) were noted. This island seemed to be all sedimentary as observed with 7 X 50 binoculars; the dips and strikes being variable from nearly horizontal to nearly vertical. We ran through two schools of porpoises. Upon arrival at Bahia San Bartolome (Turtle Bay) at 1430, all nine collectors went ashore on the north side, with no striking success. Some land shells, Miorarionta species, were collected. The only marine forms noted on the beach were Astvaea^ Purpura^ TegulCj and Aomaea -- the last two represented by living individuals. There were dead shells also of two specimens of Haliotis and some rock borers. Diptera collected on the beach included a series of a new sphaerocerid fly, named by Dr. 0. W. Richards (1963: 239- 240) as Leptooera ( Thoraaochaeta) arnaudi . The strata on this side of the bay appear to be Cretaceous but no fossils were found. About 100 feet above the present shore line there is a late Pleistocene deposit with many bay-type shells. This is overlain by about 50 feet of talus debris from the neighboring mountain. The estimate of the late- ness of the shell deposit is based upon the color retention of the shells. Around the night light great numbers of smelt milled about. Nothing would take our bait on the hooks. March 13, 1953. Friday. Bahia San Bartolome, Baja Cali- fornia Sur to Punta Abreojos, Baja California Sur. We hoisted anchor at 0600 and set course for Bahia de Ballenas. At 10 30 we passed Punta San Roque . On the way several schools of the pacific dolphin {Delphinus hairdii) and two specimens of Rhynaus were seen. One of the former was harpooned by the chief with a hand harpoon but it got under the ship and the line was cut. Later, at anchorage, Briggs had a very cold swim to cut free the entangled line from the propeller shaft. No fish struck our trolling lines. No flying fish were seen. We dropped anchor at Punta Abreojos about 16 00. Here there are two lighthouses, a large hangar, and dwellings. The water was very cold and has been so all the way down, not warmer than 58° F. Just after anchoring, six rock fish {Sehastes species) were caught. When four sea lions appeared, no more bites occur- red. One sea lion caught a fish of about three pounds and played with it a few moments before swallowing it. The bottom at anchorage is rock in four fathoms. No shore col- lecting was undertaken. Around the night light many smelt were again attracted, and two octopuses, one kelp fish, two half beaks, and three pipe fish were collected. Many large forms were seen but could not be reached. March 14, 1953. Saturday. Punta Abreojos, Baja California Sur to Bahia Santa Maria, Baja California Sur. We hoisted anchor at 0300 and set course for Bahia Santa Maria. A 14-hour run was made, with the sea being very rough until noon when it calmed down. To this point the weather has been very cold with northerly winds up to 20 miles an hour. The water has also been cold, thus we have 6 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers seen no flying fish and caught nothing on the trolling lines. We saw no porpoises and only a few sea lions all day. Birds were also scarce, but we were pretty far off shore, having lost sight of land for a time. At 1700 we passed Cabo San Lazaro Light and rounded the cape, anchor- ing in Bahia Santa Maria at 1800. At the anchorage the water was very quiet. No shore collecting was undertaken. No fish were caught at the hand lines. Only a few things appeared about the night light. A few half beaks about a foot in length were seen. The mountain mass behind our anchorage did not appear to be sedimentary in any part. Various shades of red and green are present and some of it may be serpentine. March 15, 1953. Sunday. Bahia Santa Maria, Baja Califor- nia Sur toward Cabo San Lucas, Baja California Sur. Seven collectors went ashore (with Hanna and Briggs re- maining aboard) at the Santa Maria anchorage at 0700 and a good collection of four species of reptiles and many in- sects and spiders were obtained. Burragea glabra was in bloom and this proved highly attractive to various Diptera and other Insecta. The trip's best collection of the para- sitic fly family Tachinidae was encountered at these flow- ers. Briggs and Hanna caught a number of croakers on hand lines as well as a 2 1/2-foot horn shark [Heterodontus spe- cies). A 4-foot hammer head {Sphyrna species) was also hooked and brought to the surface but it escaped. The small boat dredge was hauled several times by carrying it out from the ship and hauling aboard. The bottom was soft muddy sand but a small collection was obtained. One aba- lone shell (Haliotis) was found on shore. The weather turned warmer during the night and has been delightful since. At 1300 we hoisted anchor and set course for the overnight trip to Cabo San Lucas. March 16, 1953. Monday. Bahia Santa Maria, Baja Califor- nia Sur to Cabo San Lucas, Baja California Sur. Under way all night. At 0700 we had Cabo Falso Light abeam and made anchorage shortly thereafter at Cabo San Lucas. After clearance of the ship by Mexican officials, all collectors went ashore. The beaches are nearly barren but a good lot of small echinoids were obtained. They had recently been driven ashore. Among the Diptera collected was the robber fly {Lissoteles vanduzeei) which was rela- tively abundant on the sand dunes, a new subspecies of a minute bee fly {Mythioomyia sautellata binotata Melander, 1961: 251-252), a new species of scenopinid fly of the genus Brevitriohia (determined by Dr. Kelsey) , and a series of a new marine shore fly {Canaaeoides spinosus Wirth, 1969: 567-568). Some spiders were collected by Firstman in a house on the walls behind pictures, etc. Some of the collecting in the afternoon was done at low tide in a pool at Los Frailes Rocks where Hanna got a nice lot of chitons. A very large number of species of fishes were obtained. Many were very brilliantly colored. We appeared to be too early for reptiles. Nothing worth tak- ing was found by six night collectors. No. 86] ARNAUD: ORCA EXPEDITION 7 There is very little evidence of the great storm which hit this part of the peninsula about 15 years ago and washed the village away. There is a mark on the vegetation inland which must be at least 50 feet above sea level. March 17^ 1953. Tuesday. Cabo San Lucas, Baja California Sur. The herpetologists , Cliff, Figg-Hoblyn, Slevin, and Ball, worked hard ashore but had very mediocre success. They ob- tained a few small snakes and a few lizards, all common species. None of the rarer forms seem to be out as yet and it is agreed that we are about a month too early for this location. The entomological collections were productive as usual. Briggs, Cliff, Hanna,and Levi ton took the launch several miles southeast of our anchorage where they dropped the dredge in 4 0 fathoms. The chart said sand bottom but they hj.t rocks at once, the dredge fouled, the wire line broke and only through the fortune of having a recovery line did they save the dredge. In it were some gorgonians which were obviously rock dwellers. In the afternoon Sef- ton accompanied the group to Los Frailes Rocks (not to be confused with Los Frailes) . A fine assemblage of semi- tropical reef fishes was obtained. Upon returning to the ship, a couple of hauls with the small dredge from the ship were made with a quart of shells and sand collected. The night light attracted a variety of small fishes and squid. March 18, 1953. Wednesday. Cabo San Lucas, Baja Califor- nia Sur to Los Frailes, Baja California Sur. We left anchorage at Cabo San Lucas at 0510 and anchored at Los Frailes by 1030. Slevin and Arnaud went ashore while all other members of the party left for El Pulmo Reef. On shore, Slevin and Arnaud obtained a bat in the thatch of one of the few houses. Insects collected included repre- sentatives of two new species of minute bee flies -- two specimens of Mythioomyia ovuvalis (Melander, 1961: 201) and several hundred specimens of Mythioomyia tuhioen (Me- lander, 1961: 257-258), and a series of new robber fly {Parataraotious arenioolus Martin, 1968: 182-183) (fig. 5). Two specimens of a new genus of the parasitic fly family Tachinidae were also collected; one of which was sitting on the trunk of a fig tree {Fiaus species). The launch and two skiffs were taken by the party for the five miles to El Pulmo Reef. The arrival was about one and a half hours before a low tide, which gave the herpe- tologists time to collect a snake and several lizards. At low tide, about 1330, about 20 fish were obtained. The reef is merely a ledge of hard conglomerate dipping south- west about ten degrees and striking northwest. Boulders up to 6 inches in diameter were noted. On top of the reef there were barnacles and specimens of Chama and Aomaea. With a diving mask, Hanna went down along the leeward side, and toward the base there were gorgonians in abundance and coral heads here and there {Porites?) . These are also found over the sandy bottom between the reef and shore. It is definitely not a coral reef. On shore, Hanna found PinnUj Strombus galeatus ^ Melohgena, Murex (pink)^ Peoten 8 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers subnodosus 3 and Chama represented, along with a large cir- cular species of Ostrea, many pearl oysters and a few other bivalves, most badly worn. The headland just up the coast from the reef is old, porphyritic volcanics, judging by the shingle on the beach. The fish night light was unproductive. March 19, 1953. Thursday. Los Frailes, Baja California Sur. This was the day off for the crew of the Orca. The col- lectors went ashore at the usual time after breakfast with poor results as far as reptiles were concerned. Hanna found a good series of the large Bulimulus montezuma , all dead, around the great granite mass which forms the head- land. They were mostly in the interstices where wood rats had nests. Figg-Hoblyn collected a few immature specimens of this species under fallen tree trunks. In the afternoon Hanna and Slevin dredged out to 40 fathoms, with results that were not especially good but one chiton and many spec- imens of Calyptraea were obtained. Along the rocky shore many species of fish were collected. March 20, 1953. Friday. Los Frailes, Baja California Sur to Punta Gordas , Is la Cerralvo. We left our Los Frailes anchorage at 0600 bound for Isla Cerralvo. After leaving, the ship was slowed down while the dredge wire was played out and respooled. At about 1600 we arrived and anchored at Punta Gordas, which is on the southwestern portion of Isla Cerralvo (Ceralbo Island) . Hanna, Levi ton, Slevin, and Arnaud rowed ashore at 1630, while the other members of the party took a skiff with out- board motor to collect north of our anchorage. The motor failed and they returned after dark after a long row a- gainst the tide. The land party at the anchorage had suc- cess. In an hour, Hanna had collected about 20 specimens of Bulimulus oeralboensis and many marine shells. Pearl oysters were common on the beach. The tide was not low e- nough to collect living shells. A great number of sea hares [Dolahella) had drifted ashore and had dried leaving the shells available. Levi ton and Slevin collected about a dozen lizards including geckos. Three specimens of a new bee fly of the genus Lordotus {L. arnaudi Johnson and John- son, 1959: 13-14) were discovered. At the Oraa' s night light there were few fish but a series of marine water striders {Halobates serioeus) were collected when they came to the night light. Cerralvo is a medium-sized Gulf island some 18 miles in length and 4 1/4 miles wide. At our anchorage the rocks on shore were micaceous schist with minor granitic intrusions. Quartz seams up to 6 inches across and pockets are common, but Hanna saw no mineral segregations. March 21, 1953. Saturday. Punta Gordas, Isla Cerralvo. Our anchorage was about 1 mile southeast of Punta Gordas in 10 fathoms. In the forenoon the tide pools straight in from the anchorage were collected for fish by Briggs with the aid of other members of the party with moderate success. No. 86] ARNAUD: ORCA EXPEDITION 9 After this, Hanna and Sefton collected chitons and shells in the tide pools, and following lunch, they went to the sand pit at Punta Gordas and collected a great many beach shells, most of which were part of the rock dwelling fauna. On the low bluffs back of the beach there were huge quantities of pearl oysters, large flat ostreas, and a few pectens. This probably was a divers camp. There are conglomerate reefs jutting out from the point dipping southwest about 10 de- grees, with boulders up to 6 inches in diameter. This mate- rial is believed to be a part of the raised beach Pleisto- cene formation which in front of the anchorage is 50 feet above high tide. At the last point, it was followed up a canyon to the bed rock contact and it contained a great many shells in hard sand. Specimens of Strombus galeatus ^ Peo- ten, Maorocallista , etc. were abundant, but the rock was too hard and the shells too fragile for extraction. Evidence of mice was common and five skeletons of cats, presumably of the house variety, were found. March 22, 1953. Sunday. Punta Gordas and Isla Cerralvo to Isla Espiritu Santo . We left the anchorage at 0700 and proceeded up the west side of Isla Cerralvo to Rancho Ruffo (also known as El Mostrador) . The ship stood off because there was no salt water shallow enough to anchor and permit a swing. The Rancho is at the mouth of a very large canyon. There were three thatched shelters, a stone corral, and a well. The last is about 20 feet to water, is bricked upland has ce- ment troughs. Two large bats flew out as we came up. The place was abandoned but many turtle and goat bones indicated periodic occupancy. Collections were made up the canyon. Hanna collected about 100 land shells belonging to two species of Bulimulus , and he also collected a single speci- men of rattlesnake which later became a paratype of Crotalus enyo oevralvensis (Cliff, 1954: 82-84). Specimens of the robber fly Lissoteles vanduzeei , as well as a new species of the bee genus Pevdita (P. avnaudi Timberlake, 1958: 388), were found. All the rocks up the west side of the explored canyon appeared to be schist intruded by granitic rock. Some of the masses of granite (a gray hornblende diorite) were very large. Just north of the canyon there is a mass of sedimen- tary rock elevated to a height of about 500 feet. It con- sists of conglomerate, agglomerate, brown and white sand- stone, and limy sand. Some strata of the latter are 10 feet thick and contain fossils of various kinds. Several species of Pecten were the most common and these indicated Pliocene age. One echinoid was seen but the rock was so hard and tough that extraction was very difficult. This material ex- tends north of the canyon about 1/2 mile and up the canyon about the same distance. The collections assembled by Han- na and Slevin have been studied and reported on by Hertlein (1957, 1966) and Emerson and Hertlein (1964). The dip is eastward about 20 degrees. The heavy boulders all seemed to be the same as the metamorphic and igneous material which forms the remainder of the island. Obviously it is a block faulted up. From the ship the remainder of the island to 10 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers the northward looked to be the same schist and granite which was found to the southward. We left at 1300 and reached the indentation which sepa- rates on the east side Isla Espiritu Santo from Isla Parti- da at 1630. Hanna, Slevin, Figg-Hoblyn, and Arnaud went a- shore to collect. Rabbits must be extremely abundant judg- ing by the signs. Coming up the east side of Isla Espiritu Santo a large area of sand dunes v;as noted at the south end. The rocks from there northward for 3 or 4 miles could not be deter- mined, but they appeared to be very massive. At the first large bight with a boulder beach there is a sudden change to stratified material. This appeared to be volcanics and extends northward to the present anchorage. After we got ashore, the volcanic determination was verified, some layers being a red vitrophyre. March 23, 1953. Monday. Isla Espiritu Santo and Isla Par- tida. Isla Espiritu Santo and Isla Partida to the north are almost connected by bars (fig. 6). There are coves on each side with a bar running out from each island and a narrow, shallow channel between. Collecting was undertaken on both islands. Hanna collected numerous chitons and other marine forms at low tide. On the sand flats in the narrow channel there were windrows of minute shells washed up. Several specimens of the well known Bulimulus veseyanus as well as one small narrow one were found. Most of these were taken by Ball and Figg-Hoblyn. In addition to the shells col- lected, many others were seen. Dolium^ Strombus ^ and Pinna are used by occasional visitors for food and the shells are usually broken. Large circular ostreas and pearl oysters were common as well as several kinds of clams. These were all dead shells. The fish collectors aiding Briggs filled three gallon bottles. The herpetologists got a rattlesnake, a racer (the third known specimen of Mastioophis barbouri was collected by Figg-Hoblyn), and many lizards. Three specimens of a new scenopinid fly were collected. Dr. L. P. Kelsey has described and dedicated this new species to Mr. Sefton, naming it Saenopinus seftoni (Kelsey, 1969: 152- 153) . On the Isla Partida sandbar, several tiger beetles of the genus Cicindela were also collected. This island also yielded 6 specimens of a new therevid fly of the genus Psilooephala , near P. tepooae , as well as other desirable forms. The Captain, Chief, and Jackson went trolling and stocked the larder with sierra and skipjack (Euthynnus) . The most conspicuous rocks are the red lava at the top and the white rhyolitic ash at sea level with a black phase in between. The sea cliff just south of the anchorage is about 750 feet high. March 24, 1953. Tuesday. Isla Espiritu Santo to Isla San Francisco to Bahia de Amortajada, Isla San Jose. At 0700 we hoisted anchor and set course for Isla San Francisco. Anchorage was made there at 0900. This is a small irregular island with an area of about 1 1/2 square miles and about 100 feet high. Our anchorage on the south- No. 86] ARNAUD: ORCA EXPEDITION 11 ern end required a climb up a steep cliff (fig. 8) to make our collections. All biologists went ashore. A fair col- lection of reptiles was made. Firstman got a small rattle- snake, and Figg-Hoblyn got a spotted night snake. Figg- Hoblyn and Hanna made a thorough search for land shells and succeeded in finding only three immature and long dead shells. Three species of marine shore flies collected were new (the type series of 17 specimens of Canaseoides tenui- stylus (Wirth, 1969: 568-569), and paratypes of C. angula- tus (Wirth, 1969: 556) and C. setosus (Wirth, 1969: 565). The island was very dry. Originally San Francisco was two islands but the sea has built up a bar between the high parts. There is a salt flat on the bar now. Some salt is harvested here from five pools each about 10 by 20 feet. Along the seepage which comes through the breakwater, Hanna found a good set of Cerithidea. The island is wholly volcanic, there having been three periods of activity, each separated by an unconformity. The oldest is a rhyolitic ash consolidated into a very hard and tough white rock. Next there are flows of bright green rocks with cavities sometimes filled with milky white chal- cedony. The topmost layers are bright red, somewhat vesic- ulated lava. All the forms are agglomeratic, but it is doubtful if deposition was submarine. We left San Francisco at 1600 and arrived at Bahia de Amortajada, Isla San Jose about 1700, too late to do any work ashore. On San Jose there is a considerable establish- ment with 27 men engaged in harvesting salt from ponds be- hind the high sand beach. March 25, 1953. Wednesday. Bahia de Amortajada, Isla San Jose. Isla San Jose is 19 miles long, and 6 1/2 miles at its greatest width, with one mountain peak 2,080 feet high. All biologists went ashore after breakfast. Mammals and land birds were abundant. No snakes were seen, although there is plenty of food and cover. The herpetologists agree that we are one to two months too early for good col- lecting. Hanna found one specimen of a globose Bulimulus and Figg-Hoblyn and Ball got one also. Eight, very fragile shells of a high-spired Bulimulus were also collected. Hanna worked the hills about 2 miles back of the beach while Figg-Hoblyn and Ball went to the top of the mountains. These mountains are almost certainly granitic judging by the float which has come down from them. The frontal hills, however, are all volcanic, mostly reddish brown andesite with a minor amount of green. The age is very uncertain, but the island has no resemblance geologically to the beau- tifully stratified section exposed on the adjacent penin- sula. In the afternoon, Hanna, Briggs, and Wall went out in the launch dredging, and after making 2 hauls on sand bottom the motor stopped and they were lucky to get back to the ship. The water pump had failed. Nevertheless they got an excellent collection of small shells. Good spider collections were made by Firstman. Among the many insects collected was a single specimen of the parasitic fly family Tachinidae which was designated as a 12 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers paratype of Musaopteryx petensis (Reinhard, 1958: 280). It was collected on the leaves of ironwood. A series of spec- imens of the bee fly Lordotus gunoeus provided a 600 mile southward extension to its recorded range. March 26^ 1953. Thursday. Bahia de Amortajada, Isla San Jose to Isla Santa Cruz to Bahia Agua Verde, Baja Califor- nia Sur. We left Isla San Jose at 0700 and reached Isla Santa Cruz about 0900. All biologists went ashore. The Oroa did not anchor, but stood off and waited for us. Santa Cruz is a steep rugged island a little less than 4 miles long, about 1 1/2 miles wide, and about 1500 feet high. It is deeply cut by many canyons, the erosion of which indicates great precipitation at one time. Isla Santa Cruz is entirely a granodiorite with aplite dikes and a few veins of quartz up to 8 inches thick. Some epi- dote and copper-stained rock was picked up as float and north of our southwest landing place there is a zone which from the ship looked like it might be highly mineralized. No sedimentary or volcanic rocks were noted. We found three Mexicans camped ashore in a cave. They were fishermen and said they spent about 3 months each year here. The surrounding waters were literally alive with fish. The only land bird seen was a hummingbird. With the help of Figg-Hoblyn, Ball, and Arnaud, Hanna got over 100 specimens of Bulimulus santaaruzensis . Slevin found the skeleton of a snake. This was a new distributional record. Insects were relatively scarce. Only about 50 specimens were collected. The party was picked up at 1150. On the way to Bahia Agua Verde we coasted along the east side of the peninsula, pretty far out, but with glasses the shore line looked like a great escarpment with beautifully exposed stratification. This is probably the same volcan- ics as at Bahia Agua Verde. The exposed rocks are reddish brown volcanic agglomerate. We arrived at Bahia Agua Verde at 1530 and rowed ashore and started to collect by 1600. There are several large palms around the small village. Members of the party ashore worked up a canyon on the north side of the great stream valley where Hanna found about 100 specimens of Bulimulus. Mr. Sefton took about a dozen chitons, and there was fair success in collecting fish. There were many insects flying about a mesquite tree in bloom, and about 700 specimens were collected. The insects collected included 2 species of small bees of the genus Perdita (P. punotosignata punotosignata Cockerell and the new species P. dupliaans Timberlake) as well as the unique holotype male of the small bee fly Mythioomyia aperta (Melander, 1961: 183). March 27, 1953. Friday. Bahia Agua Verde, Baja California Sur to Isla Santa Catalina to Bahia Ballandra, Isla de Car- men. At 0700 we hoisted anchor and set course for Isla Santa Catalina, arriving at a poor anchorage beside a boulder spit on the northeast side of the island at 0900, anchoring in 8 fathoms. This is another rugged island, about 7 1/2 No. 86] ARNAUD: ORCA EXPEDITION 13 miles long, 2 miles wideband 1^500 feet high. At the land- ing place the rocks were of many kinds — granite with feldspar and epidote dykes, shist of many forms, and at least one thick mass of crystalline limestone. Samples were taken of the various forms. No sediments were seen. A primitive landing strip had been cleared across the in- side flat area of the boulder spit. Firstman, Briggs , and Cliff collected specimens of a new species of rattlesnake, described as Cvotalus oatalinensis by Cliff in 1954. In turning over rocks Levi ton was stung on the finger by a small slender-tailed scorpion, without serious consequence. A single web-spinner of the order Embioptera was collected under a large rock, the first re- cord of this order from this island. Slevin collected a tenebrionid beetle in alcohol before returning to the Oraa. On the return to the ship a live maggot was discovered and removed from the alcohol, having emerged from the beetle. The maggot pupated with a female sarcophagid fly later emerging. Over 220 specimens of a new marine shore fly {Canaceoides setosus Wirth, 1969: 565-567) (fig. 9) were swept from coastal rocks. With the help of Levi ton, Hanna collected both Bulimulus johnstoni and Pupoides oatalinen- sis which have been reported. They also found a specimen of Gastrooopta, which Figg-Hoblyn and Arnaud also collected. The shells of Bulimulus were everywhere -- they were more abundant than Hanna had ever known land shells to be. Live ones were under the first rocks in slides, and he often took 4 to 6 off one rock. The only evidence of mammals was one cat skull picked up by Hanna, and Figg-Hoblyn saw a dead cat. The collecting party was called off shore and departed at 1330 and set course for Bahia Ballandra, Isla de Carmen. As seen from the Oroa far out to the east, the south end of Carmen seemed to be sediments dipping south about 30 degrees. We rounded the north point and coasted down the west side of the island to the pretty little landlocked Bahia Ballandra, noting only what appeared to be volcanics except for an occasional light patch of sediments of very small extent. We arrived and made anchor at 18 30. There is only one house at the bay. No shore collecting was undertaken. March 28, 19 53. Saturday. Bahia de Ballandra, Isla de Car- men, to Loreto, Baja California Sur. The collectors all went ashore after breakfast. Mr. Sefton made a fine collection of intertidal chitons in the bay. Briggs, Cliff, Wall, and Hanna seined a mangrove pool back of the beach and took about 50 fish in half an hour. Briggs, Cliff, Levi ton, Slevin, and Hanna worked on the reef most of the forenoon. It is exposed on the beach to an elevation of about 50 feet and appears to be Pleistocene; some of the shells, such as those belonging to Glycymeris gigant&a , still retain a little color,, and the assemblage is the same as those living in the area at the present time. This particular reef is on the south side of the bay. On the north side there is first a mangrove swamp, then a flat valley with a canyon at the head. On the borders of this 14 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers little valley there are similar reefs, 5 of them on each projecting point and at the head there is an obvious old beach line. The bounding basement rocks are rhyolites and possibly andesites. Chalcedony seams are common at the head of the valley. Near the first-mentioned reef and on the beach cliffs there are seams or veins of a white miner- al. In the afternoon Briggs, Leviton, Wall, and Hanna went dredging outside the bay and made four hauls in 25-35 fathoms. The bottom was muddy sand with much broken shell. Some good mollusks were obtained, but in general it was dead bottom. The Captain and Chief caught a fine lot of fish in the forenoon by trolling near shore. One was a 30-pound grouper. Figg-Hoblyn, Ball, and Arnaud hiked over- land (figs. 10-12) to the ridge which overlooks the exten- sive salt works. They met several residents with their loaded burros on the trail. The entomological collecting at mesquite flowers, along the mangroves , and along the shore resulted in the discovery of 5 taxa of minute bee flies, Mythioomyia , including the unique male type of M. munda (Melander, 1961: 228-229), the paratype series of M. vhaeha (Melander, 1961: 246-247) and M. tenthes (Melander, 1961: 253-254), the allotype of M. soutellata hinotata (Melander, 1961: 251-252) , and M. soutellata Coquillett. Left anchorage at 16 00 and anchored at Loreto, Baja California Sur, on a very quiet and glassy sea at 1800. The younger members of the expedition rowed ashore after dinner to the very dark beach and visited the town. March 29, 1953. Sunday. Loreto, Baja California Sur. This was lay day for the crew and only limited work was done ashore. Slevin and Jianna stayed aboard and got their collections attended to and equipment repaired and altered. It was a generally cloudy day with wind, which whitecapped the Gulf at the anchorage in the afternoon and early even- ing. Figg-Hoblyn, Ball, Wall, and Arnaud went ashore about 0900. They met a bearded American who gave them a short ride about town in his "command" car. They visited the old mission which was in the process of being restored. After collecting they had dinner and a few beers at the modern Sportsmans Lodge. In the evening there was a dance in the town square. A borrego (bighorn sheep, Ovis oanadensis) was kept on a rope as a pet at one of the houses. March 30, 1953. Monday. Loreto, Baja California Sur to Isla Ildefonso to Punta Pulpito, Baja California Sur. We hoisted anchor at 0700 and set course for Ildefonso, on a bright sunny day. The sea was whitecapped due to a brisk head wind. There was a sheltered lee at the south- east end of Ildefonso where we dropped anchor at noon, and the biologists rowed ashore by 1230. This is a small is- land, a little more than a mile long, about half a mile wide, and attains a height of 387 feet, the top being rather flat. The island is volcanic with many caves and cliffs. Apparently an agglomerate at an elevation of about 100 feet represents an old beach deposit but it contained no shells. In some of the rocks there are irregular masses of white No. 86] ARNAUD: ORCA EXPEDITION 15 chalcedony. Copper stains were noted in a few places. Ob- sidian fragments were found over the lower southern slopes but no source could be found. It was not a pure material but was not incrusted or weathered. It may have been car- ried there by egg hunters. Bushes of Sympetaleia aurea were conspicuous with their orange flowers. There was some fresh water caught in rock basins, and Figg-Hoblyn collected two mosquitoes. Hanna was bitten by mosquitoes quite a few times and reported later that these produced good sized welts. The herpetologists got two lizards and a gecko. Tide pooling resulted in 2 gallons of small fish, and the Captain and Chief caught 7 groupers. A thorough search for land shells was made, but none found. Several bags of fine material were taken to search for small species. Insect and spider collecting was excellent. Over 370 specimens of a new species of marine shore fly, described by Dr. W. W. Wirth as Canaaeoides sGutellatus (1969: 563-569), were swept from coastal rocks. Collections also included a new species of therevid fly of the genus Fhevoceva. There was a large colony of Heermann's Gulls {Larus heermanni) on the southern slope. Blue-footed Boobies {Sula nehouxii) (fig. 13) nested on the cliff and had young. The gulls and pelicans had not laid eggs. A sparrow and a kingfisher were seen. A young Osprey {Pandion haliaetus) (fig. 14) in a nest was photographed while a parent circled overhead. We hoisted anchor at 16 30 and anchored at Punta Pulpito, Baja California Sur at 1745. After dinner, Hanna and Slevin went ashore on the south side and with a flashlight collected specimens of several species of fossil Mollusca. In the Pulpito cliff, south side, there is a mass of vein-like black crumbly obsidian. This vein shows in the photograph (fig. 15) . Since all the fos- sils seen were in sea cliffs and thus hard to collect, it was decided to stay another day to hunt for some canyons which have weathered down to the fossil bearing strata. March 31, 1953. Tuesday. Punta Pulpito, Baja California Sur to Isla San Marcos. The collecting parties left the Oroa before 0800. The morning was mostly overcast and cool. Cliff, Slevin, and Hanna went northwest on the tableland until they came to a canyon, about a mile back, which had cut down into the fos- sil-bearing beds. There was an unbelievable number of fos- sils, the most conspicuous belonging to a large species of Peoten and to Dosinia, but many other groups were repre- sented. Many forms seemed to have grown to larger size than at present. One poorly preserved abalone was found. It appears to be referable to Haliotis fulgens (Hertlein, 1957: 68-69). This is the first specimen recorded with certainty as a fossil from the Gulf of California. Small forms were scarce. Only a few echinoids, representing 3 species, were collected. The beds are nearly horizontal and are faulted off on the east toward the Punto Pulpito which forms a large and very conspicuous promontory. Whether they are faulted on the landward side could not be determined in the available time. The insect collecting included 2 species of scenopinid fly -- a new species of 16 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers Bvevitriohia and Metatriohia huthosa and 4 new species of minute bee flies -- the unique holotype of Mythioomyia gynandra (Melander, 1961: 211), the holotype and 2 speci- mens of M. humeralis (Melander, 1961: 213-214) and para- types of M. annulata (Melander, 1961: 181-182) and M. ir- rupta (Melander, 1961: 218-219). The shore parties re- turned to the Oroa at 1100. By 1130 we were under way and set course for Isla San Marcos. We dropped anchor at the southwest end of Isla San Marcos at 1630. Figg-Hoblyn and Ball left at once for the northern part of the island. They found about 15 specimens of Bulimulus , 3 of which were alive, and reported a great profusion of flowers, estimated at 40 different kinds. When they returned to the ship at 20 30, Ball was ill, probably from overexertion on the hike. Leviton, Hanna, and Arnaud also went ashore for 1 hour of collecting about the boat landing. On the conglomerate which forms the southwest corner of the island they col- lected about 50 specimens of Bulimulus , 1 gecko, and some insects . The gypsum for which this island is famous is found well distributed over the south end and samples of it were col- lected. The quarries which are operated commercially were not visited. Isla San Marcos is almost 6 miles long and 2 1/2 miles wide; its highest peak being slightly less than 900 feet. April 1, 1953. Wednesday. Isla San Marcos to Isla San Esteban. We hoisted anchor at 0615 and set course for Isla San Esteban. After a long run through glassy calm seas we ar- rived at San Esteban at 1700, south side. San Esteban is about 4 miles long, 3 miles wide, and attains a height of 1,772 feet. East of our anchorage, rip tides, due to fast \ tidal currents, caused whitecrested turbulent water. The shore was a boulder beach, quite barren of chitons and bar- nacles. Evidently it is a severe beach in a southwest storm. There is much evidence of volcanic activity ashore, but at the landing there were some fossiliferous layers, the fossils not being well preserved or easy to get out. The beds are tipped at a high angle and have boulder beach deposits on top. A wide canyon extends back into the cen- ter of the island. In an hour ashore, Hanna collected 2 representatives of Miorarionta under volcanic slabs on the west side of the canyon as well as a lot of pupillids. Some insects and reptiles were also collected. One was a snake which Figg-Hoblyn collected at night. It was a calm night with cool air. April 2, 1953. Thursday. Isla San Esteban. The temperature is now cooler. At 0700, it was 58° F. in the pilot house, and the water temperature was 60° F. This day was cool with only a slight wind. All biologists went ashore early. Figg-Hoblyn, Firstman, Hanna, and Arnaud collected up the main canyon to the north (figs. 16 and 17) about 2 1/2 miles expecting to find water, but there was none. There had been a little rain not very long ago, but evidently there was no runoff. There was some No. 86] ARNAUD: ORCA EXPEDITION 17 moisture down about 6 inches below the surface and many of the plants were in flower. The elephant trees, however, had seed almost ripe and the agaves had dried stalks. The very docile chuckwalla, Sauvomalus varius (fig. 18) was abundant. They could be easily picked up by hand without the collector being bitten. Live specimens of these were collected for display at the San Diego Zoo and elsewhere. In retrospect, these should not be collected for this pur- pose and they should be a protected species. A few speci- mens of the "aggressive" Ctenosaura hemilopha were seen and photographed. Several geckos and two racers were collected by the herpetologists . Insect and spider collecting was productive. One of the two minute bee flies collected proved to be new to science, being described as Mythioomyia fumipennis (fig. 19) by Melander (1961: 207-208) from the unique holotype. Later in the day, Hanna and Levi ton dug a deep hole in a rock slide on the west side of the canyon and collected about 40 specimens of Miarariontas , but still they could not find any living ones. The island has some fossil-bearing beds at the south anchorage which may be as old as upper Pliocene, but the fossils are very poorly preserved. It is difficult to be- lieve that all of the erosion which is evident in the main canyon could have taken place without a geological period of heavy rainfall. There are box canyons cut in hard vol- canic rock 40 feet deep. April 3, 1953. Friday. Isla San Esteban to Isla San Pedro Martir to Bahia San Pedro, Sonora. We hoisted anchor after 0600 and arrived at Isla San Pedro Martir about 0830 (fig. 21) . The Oroa stood off while the biologists went ashore. There is no good landing where the cliffs can be scaled, so that the collectors went ashore from the skiffs by jumping out on rocks. This is a bird island with much evidence of guano collecting in the past. It is a small high island, being somewhat triangular in shape and less than a mile across and more than 1,000 feet high. The island is wholly volcanic with patches of stratified material interbedded with massive flows. The chemical effect of the guano on the volcanic rocks is very interesting. It has modified the rocks and altered their composition profoundly. Judging by the extent of this alteration it would seem that it has been a bird island for a long time. California sea lions have 2 rookeries on the island, which together probably number at least 1,000 ani- mals. No land shells were found, but in the detrital ma- terial brought back to the Oraa 1 specimen of Gastrooopta was found. On the upper slopes there is a fine cactus for- est of Paahy cereus pringlei . A limited collection of in- sects was made which included a few large weevils. A strong wind developed and the landing parties were recalled by ship whistle at 1130. It was a rough sea to board the skiffs from the rocks and row back to the ship. We then set course for Bahia San Pedro, Sonora, where we arrived and dropped anchor at 1800. The night lights attracted many fishes heretofore not seen. Ball, Figg-Hoblyn, First- man, Wall, and Arnaud went ashore for night collecting, 18 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers with only limited success. April 4, 1953. Saturday. Bahia San Pedro, Sonora to Guay- mas , Sonora. The rocks at Bahia San Pedro are ancient volcanics with much alteration. A few representative samples were taken, including one which looked like a half obsidian. It was part of a two foot vein in red altered volcanics at the northeast end of the bay. It was an overcast cold morning. Mr. Sefton took a fine series of chitons on the low tide. He also decapitated a porpoise which was found floating in the bay the previous night and which he had tov/ed ashore. It had large teeth which were heavily worn. The last tide pool collecting was done by Briggs with the help of the herpetologists . Be- cause of the weather, no reptiles were out except for a few lizards. A search was made for specimens of Bulimulus by Hanna, and a few were found among the boulders in the old stream bed of the large canyon which comes into the north- east corner of the bay. At noon we left Bahia San Pedro for the port city of Guaymas . The trip down the coast was with a heavy follow- ing sea. We arrived after 1600. April 5, 1953. Sunday. Guaymas, Sonora. Four of the Stanford biologists, Briggs, Cliff, Firstman, and Leviton, together with Ball, left by bus for their home destinations. Figg-Hoblyn and Arnaud hiked into the hills northeast of Guaymas where they collected insects with good results. Specimens of a new genus and species of mite gall maker, Para-phytoptella avnaudi (Keifer, 1959: 17-18), were collected. These mites caused clusters of bead galls on the leaves of the white-flowered shrub Covdia parvi folia. A few land snails [Bulimulus species) and 2 pupillids were also collected. Hanna and Slevin invited Sefton, Figg- Hoblyn, and Arnaud out to dinner in Guaymas in the evening. The collections made by the Stanford group of biologists were left aboard the Oroa. They were to be transported on April 16 by the California Academy of Sciences vehicle which was to pick up Hanna and Slevin and their collections. This was the conclusion of the first part of the Sefton Oraa Expedition. Part II. April 6 - 17, 1953 April 6, 1953. Monday. Guaymas, Sonora. The last two Stanford biologists, Figg-Hoblyn and Arnaud, left by bus in the morning for a short visit to Hermosillo, on their return trip to California. Arnaud carried the in- sect collection in a suitcase for safe transport. They also carried several live specimens of Sauromalus varius as part of their baggage. Dr. Rolf Bolin, ichthyologist from Stanford University's Hopkins Marine Station at Pacific Grove, arrived at Guaymas in the evening, as well as two fishermen from San Diego. No. 86] ARNAUD: ORCA EXPEDITION 19 April If 1953. Tuesday. Guaymas , Sonora. The Ovoa was in port. Hanna was recovering from a mild case of food poisoning presumably obtained at the dinner in Guaymas. April 8, 1953. Wednesday. Guaymas, Sonora to Bahia de Santa Inez, Baja California Sur. The Oroa left Guaymas at 0600. There was a brisk north wind on the day's crossing of the Gulf. On the way deep plankton hauls were made. In the first, with a fine mesh, a half gallon of miscellaneous pteropods and crustaceans were collected. Arrived at Bahia de Santa Inez, Baja Cali- fornia Sur, at 1700. The fishermen caught 2 sharks and 2 bone fish before dark. April 9, 1953. Thursday. Bahia de Santa Inez, Baja Cali- fornia Sur. Bolin and Sefton collected fish on shore all day and took representatives of 27 species in tide pools. The sport-fishermen, George and Doc, went out to Isla Santa Inez trolling and came back with 34 groupers. The Captain and Chief also got 7. Slevin and Hanna worked ashore and obtained a good collection of shells -- living. Pleistocene, and Pliocene. The living or recent shells were piled in windrows on the beaches. The Pleistocene covers an elevated bench up to 50 feet which extends inland about 3/4 of a mile. In places it is 6 feet thick solid shells, calcareous algae, and coral. A great many species are present, appar- ently all living today. Although present, representatives of the heavy species of Spondylus , Chama, the round form of Ostrea^ Stromhus ^ and Fasaiolaria were not collected. The Pliocene underlies this and forms the low hills behind the bay. It is brown limy sand with the shells nearly all dis- solved away. The rock was so tough and hard that it was difficult to dig into, but collections were made of some pectens and echinoids which were well preserved. April 10, 1953. Friday. Bahia de Santa Inez, Baja Califor- nia Sur. The biologists and Sefton worked ashore, collecting shore fishes, shells, etc., and taking photographs. Speci- mens representing 2 species of Vermetus were found. One, a very small form, grew in great head-like clusters at about mid-tide. The fishermen, George and Doc, and Jackson went fishing and returned with 30 fish, mostly groupers. April 11, 1953. Saturday. Bahia de Santa Inez, Baja Cali- fornia Sur to Bahia Coyote, Bahia Concepcion, Baja Califor- nia Sur. The Oraa went out into deep water in the early morning to make deep plankton hauls for Bolin. The wind freshened farther from shore, so that but 1 haul was made with 4,000 feet of line. The result was 4 small lantern fish. By the time the net was brought in, a strong north wind of about 30 to 40 miles was blowing and the sea was so rough that further work was impractical. Anchorage was sought there- fore in the small well protected Bahia Coyote, and all went 20 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers ashore. Collections were made mostly around the mangrove lagoon on the west side. In the lagoon there was a heavy growth of coral and on the mangrove roots there were great clusters of oysters. The latter were also attached to the surrounding rocks. Kitchen middens were very extensive and very deep, especially next to the cliffs of volcanic agglom- erate. This is mostly andesite blocks up to several feet in diameter, apparently the toe of a very massive flow. In one place a 6-inch seam of yellowish opal was observed. April 12, 1953. Sunday. Bahia Coyote, Bahia Concepcion, Baja California Sur. Bolin, Slevin, and Hanna went to a small island (no name) near the anchorage this morning, but found no land shells. Two geckos and 2 lizards were obtained. They then pro- ceeded to Isla Coyote farther out and found specimens of a Bulimulus species to be exceedingly abundant. Over 100 specimens were obtained, as well as some geckos and lizards. In the afternoon they returned to the mangrove lagoon and with a boat inside took many fine specimens of several species of fishes in the growths about the mangrove roots. The wind was strong all day but at night it was dead calm. April 13, 1953. Monday. Bahia Coyote, Bahia Concepcion, Baja California Sur. Bolin, Slevin, and Hanna dredged in the morning, making hauls in Bahia Coyote and across Bahia Concepcion at that point, using the launch. Depths ranged from 2 to 16 fath- oms. In every case the bottom was the same broken and dead shells, sand and mud. It was detrital material washed out from near shore, indicating that the whole bay is a drowned valley. In the afternoon the Ovoa moved to the head of Concepcion. There in the mangrove lagoon 10 species of fish were obtained. On shore in several places there were heaps of relatively fresh large Strombus shells which had been broken open by natives who use the animals for food. April 14, 1953. Tuesday. Bahia Concepcion, Baja Califor- nia Sur to San Inez, Baja California Sur. Left anchorage in morning and made the run to Bahia de Santa Inez in order to have a good start for Guaymas on the 15th. At Santa Inez Bay, Bolin and Hanna went ashore in the afternoon to check the Pliocene farther inland to try to get some good, well preserved fossils, but failed. The beds are consolidated to a hard, tough, impure lime with nearly all fossils dissolved out. Favorable preservation, it was thought, could be found in the area and would be very important. However, it would be necessary to have enough time so that a careful search could be made. What appeared to be fragments of Peoten keepi and other striking Pliocene forms were seen. Wind continued to blow about 20 miles per hour even in the evening. Packing was practical- ly completed preparatory to going ashore on the morning of the 16th. April 15, 1953. Wednesday. Bahia de Santa Inez, Baja Cal- No. 86] ARNAUD: ORCA EXPEDITION 21 ifornia Sur to Guaymas , Sonora. Departure was made at midnight to try to avoid the strong winds which spring up about 1100 each day. At day- light a fairly successful 100-fathom plankton haul was made, There were several lantern fishes and some other forms. The trip across the Gulf was rough. The nearly constant strong winds encountered in this part of the Gulf had been totally unexpected. Upon arrival at Guaymas , the remainder of the day was spent getting the collections and gear in order to be put ashore as soon as Mr. A. E. Gundred of the California Academy of Sciences arrived. April 16, 1953. Thursday. Guaymas , Sonora. The California Academy of Sciences and the Stanford Uni- versity collections were loaded in the Academy's panel truck which was driven to Guaymas by Alvin Gundred follow- ing his arrival at 14 30. This was a very heavy load, too heavy in fact, and the next day out of Hermosillo it was necessary to dump the formaldehyde out of all fish and rep- tile containers to lighten up. Bolin, Slevin, Gundred, and Hanna left Guaymas at 0600 on the 17th, and after tire trouble in Magdalena, arrived in Casa Grande, Arizona, at 2200. On the 18th the party returned to San Diego via Yuma and reached San Francisco on the morning of the 20th. April 17, 195 3. Friday. Guaymas, Sonora. At this time the University of California, Los Angeles, group joined the Ovca for work in the Gulf and returned to San Diego at the beginning of May. The work of this third part is not treated in this account. SUMMARY Significant collections were made by all scientific per- sonnel. Some collections formed part of research studies which were published almost immediately, see Cliff (1954), while other portions of the collections have been utilized in revisions and monographs, often from larger geographical areas, as in the Diptera, see Melander (1961) and Wirth (1969). It will be many decades, however, before all spec- imens have been studied and described, particularly when considering the insects collected. The collections are deposited in a number of scientific institutions, and these are as follows: fossils, mollusks, and other marine invertebrates collected by Dr. G Dallas Hanna are deposited in the collections of the Departments of Geology and Invertebrate Zoology of the California Acad- of Sciences; the reptiles collected by Mr. Joseph R. Slevin are deposited with the Department of Herpetology, California Academy of Sciences; the fishes collected by John C. Briggs and scientific personnel are deposited with the Stanford Fish Collections at Stanford University; the reptiles col- lected by Frank S. Cliff, Alan E. Leviton, and John P. Figg- Hoblyn were deposited with Stanford University and have recently been transferred to the California Academy of Sciences; the spiders, scorpions, and allies collected by 22 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers Bruce L. Firstman were deposited with the American Museum of Natural History in 1962; the Coleoptera collected by John P. Figg-Hoblyn and the Diptera and other insects col- lected by Paul H. Arnaud, Jr. , were primarily donated to the Department of Entomology, California Academy of Sci- ences, in 1954. The collections made by Arnaud and presented to the Academy totaled 5,9 7 8 pinned specimens (of these, ^5 80 were pinned while aboard the Oroa) . In addition, some series of ants and a few scorpions preserved in alcohol and donated to the California Academy of Sciences are not included in this total. Entomological specimens distributed elsewhere are as follows: collections of scale insects (Homoptera) presented to the late Prof. G. F. Ferris, Stanford Univer- sity; gall forming mites (Eriophyidae) presented to Mr. H. H. Keifer, California Department of Agriculture, Sacramento; a duplicate series of bees of the genus Ferdita presented to Mr. P. H. Timberlake of the University of California, Riverside; a large series of duplicate marine Dolichopodi- dae of the subfamily Aphrosylinae from Isla San Geronimo presented to Mrs. Marian Adachi Cohen, of the University of Hawaii, Honolulu; duplicate marine shore flies of the fam- ily Canaceidae presented to Dr. Willis W. Wirth, of the United States National Museum; and a small collection of about 100 Tachinidae and a similar number of insects col- lected at Guaymas are retained in the Arnaud collection. LITERATURE CITED CLIFF, F, 1954. EMERSON, 1964. HANNA, G 1925. HERTLEIN, 1957. 1966. JOHNSON, 1959. S. Snakes of the islands in the Gulf of California, Mexico. Transactions of the San Diego Society of Natural History, vol. 12, no. 5, pp. 67-98, pis. 6 & 7, figs. 1-4. W. K., and HERTLEIN, L. G. Invertebrate megafossils of the Belvedere expedi- tion to the Gulf of California. Transactions of the San Diego Society of Natural History, vol. 13, no. 17, pp. 333-368, figs. 1-6. D. Expedition to Guadalupe Island, Mexico, in 1922. General report. Proceedings of the California Academy of Sciences, 4th ser., vol. 14, no. 12, pp. 217-275, pis. 15-19, text figs. 1-2. L. G. Pliocene and Pleistocene fossils from the south- ern portion of the Gulf of California. Bul- letin of the Southern California Academy of Sciences, vol. 56, pt. 2, pp. 57-75, pi. 13. Pliocene fossils from Rancho El Refugio, Baja California, and Cerralvo Island, Mexico. Pro- ceedings of the California Academy of Sciences, 4th ser., vol. 30, no. 14, pp. 265-284, figs. 1-17. D. E., and JOHNSON, L. M. Notes on the genus Lordotus Loew , with descrip- No. 86] ARNAUD: ORCA EXPEDITION 23 \ KEIFER, 1959 KELSEY, 1969 LINDSAY, 1952. MARTIN, 1968 MELANDER, 1961. REINHARD, 1958. RICHARDS, 1963. SLEVIN, J 1923. TIMBERLAKE, 1958. i^ WIRTH, W. 1969. tions of new species (Diptera: Bombyliidae) . The Great Basin Naturalist, vol. 19, no. 1, pp. 9-26. H. H. Eriophyid studies XXVII. Occasional Papers, Bureau of Entomology, California Department of Agriculture, no. 1, pp. 1-18, pis. 1-12. L. P. A revision of the Scenopinidae (Diptera) of the world. United States National Museum Bulletin, no. 277, pp. i-v, 1-336, figs. 1-208. G. E. The Sefton Foundation - Stanford University expe- dition to the Gulf of California, 1952. Re- printed by Belvedere Scientific Fund [Califor- nia Academy of Sciences] , San Francisco, Cali- fornia, pp. 1-98, map. . H. New Mexican AoTonyohes and Parataractious (Dip- tera: Asilidae) . The Pan-Pacific Entomologist, vol. 44, no. 3, pp. 179-183. A. L. The genus Mythioomyia (Diptera: Bombyliidae) . The Wasmann Journal of Biology (1960), vol. 18, no. 2, pp. 161-261. H. J. North American Tachinidae (Diptera) . Journal of the Kansas Entomological Society, vol. 31, no. 4, pp. 277-284. O. W. Sphaerocerid flies from South and Central America in the collection of the California Academy of Sciences (Diptera) . The Pan-Pacific Entomolo- gist, vol. 39, no. 4, pp. 231-246, figs. 1-14. Expedition of the California Academy of Sciences to the Gulf of California in 1921. General account. Proceedings of the California Academy of Sciences, 4th ser. , vol. 12, no. 6, pp. 55- 7 2 , map . P. H. A revisional study of the bees of the genus Per- dita F. Smith, with special reference to the fauna of the Pacific Coast (Hymenoptera, Apoidea) Part III. University of California Publications in Entomology, vol. 14, no. 5, pp. 303-410, pis. 4-15. W. The shore flies of the genus Canaceoides Cresson (Diptera: Canaceidae) . Proceedings of the California Academy of Sciences, 4th ser., vol. 36, no. 19, pp. 551-570, figs. 1-36. No. 86] ARNAUD: ORCA EXPEDITION 25 FIGURE 1. Research ship OToa. the late Mr. Sefton. Photograph furnished by 26 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers FIGURE 2. Route of the 1953 Sefton Ovca Expedition, Parts I and II, to the Gulf of California. The localities are indicated by numbered circles and are as follows: Part I. March 9 - April 5, 1953 1. San Diego, California (9 March) 2. Cabo Colnett, Baja California Norte (9 March) 3. Isla San Geronimo (10 March) 4. Bahia del Sur, Isla de Cedros (11 March) 5. Bahia San Bartolome, Baja California Sur (12 March) 6. Punta Abreojos, Baja California Sur (13 March) 7. Bahia Santa Maria, Baja California Sur (14, 15 March) 8. Cabo San Lucas, Baja California Sur (16, 17 March) 9. Los Frailes, Baja California Sur (18, 19 March) 10. Punta Gordas , Isla Cerralvo (20, 21 March) 11. Isla Espiritu Santo, Isla Partida (22, 23 March) 12. Isla San Francisco (24 March) 13. Bahia Amortajada, Isla San Jose (24, 25 March) 14. Isla Santa Cruz (26 March) 15. Bahia Agua Verde, Baja California Sur (26 March) 16. Isla Santa Catalina (27 March) 17. Bahia de Ballandra, Isla de Carmen (27, 28 March) 18. Loreto, Baja California Sur (28, 29 March) 19. Isla Ildefonso (30 March) 20. Punta Pulpito, Baja California Sur (30, 31 March) 21. Isla San Marcos (31 March) 22. Isla de San Esteban (1, 2 April) 23. Isla San Pedro Martir (3 April) 24. Bahia San Pedro, Sonora (3, 4 April) Part II. April 6-16, 1953 25. Guaymas, Sonora (4-7, 16 April) 26. Bahia de Santa Inez, Baja California Sur (8-10, 14 April) 27. Bahia Coyote, Baja California Sur (11-13 April) 28. Bahia Concepcion, Baja California Sur (13 April) No. 86] ARNAUD: ORCA EXPEDITION 27 UNITED STATES MEXICO 115 110° 28 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers FIGURE 3. Mr. Slevin, on left and Dr. Hanna on right, aboard research ship Oroa, off Pacific coast Baja Califor- nia. FIGURE 4. Left to right, Engineer McNeilage, Captain Ellis and crewman Wall, on bridge Oroa. No. 86] ARNAUD: ORCA EXPEDITION 29 HaTk .A : ^ -^ ->■£fess-■«|J^ '^t-4^- ^"^. -.-. i 0- i4 FIGURE 5. A robber fly, Parataratiaus areniaola Martin, Los Frailes, Holotype male. FIGURE 6. Oraa at anchorage, looking east from Isla Espiritu Santo on right and Isla Partida on left. 30 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers FIGURE 7. A scenopinid fly, Scenopinus seftoni Kelsey, Isla Espiritu Santo, Holotype male. FIGURE 8. Rowing back from shore collecting, Isla San Francisco, left to right, Mr. Slevin, Ball, Figg-Hoblyn, Cliff, Levi ton, and Briggs . No. 86] ARNAUD: ORCA EXPEDITION 31 FIGURE 9. Marine shore fly, Canaoeoides setosus Wirth, Isla Santa Catalina, Holotype female. FIGURE 10. Interior of Isla de Carmen, facing west to- ward Puerto Ballandra. 32 CALIFORNIA ACADEMY OF SCIENCES [Occ. Papers .««.«if>