244
MALCOLM R. CLARKE
The breeding season must extend over a long period because
larvae of less than 0.5 cm in length are present off West Africa from
March to October. Size distributions for the various months suggest
that most of the spawning takes place in winter. In October the squids
are half grown and they are thought to mature and breed the following
winter and then perhaps die (Bruun, 1943). However, this cannot be
regarded as settled because the division of the size distribution into
size groups can only be described as arbitrary.
A specimen was taken from the mouth of a deep-sea fish (Dall).
XXI. DISTRIBUTION
As pointed out in the introduction, our knowledge of the group is
probably not good enough to draw general conclusions concerning the
relationships between the cephalopod fauna of different geographical
areas. However, it is perhaps useful to list the species recorded from
general areas (Table 111, Fig. 55). Boundaries of these have been
rather arbitrarily chosen and are useful for descriptive purposes rather
than for marking any real faunistic barriers; in most cases their
position has been determined by geographical expediency. To some
extent the total number of species and the number of “endemic”
species in any area is related to the amount of work done in that area
(cf. Table I11 and Fig. 1).
The distribution of a few of the better known species is worth
noting as they are oegopsid representatives of previously recognized
types. Hyaloteuthis pelagicus, Onychoteuthis banksi, Ommustrephes
bartrami, Onychia carribaea, Thysanoteuthis rhombus, Brachioteuthis
riisei, Lycoteuthis diadema, Cranchia scabra and the sepioid Spirula
spirula are widespread in warm and temperate waters. Bathyteuthis
abyssicola, Abraliopsis morissi and Histioteuthis bonellii are found
in the Atlantic and Indian Ocean. Symplectoteuthis oualaniensis (both
forms) and Abralia andamanica are found in the Indian Ocean and the
Pacific. Better known species which are restricted to particular oceans
are in the North Atlantic Illex illecebrosus, in the North Atlantic and
the Mediterranean Ommastrephes caroli, Illex coindeti and Abralia
veranyi, in the North and South Atlantic and Mediterranean Ommastrephes pteropus, Todarodes sagittatus and Todaropsis eblanae, in the
Indian Ocean Brachioteuthis picta and in the Pacific Symplectoteuthis
luminosa, Todarodes paci$cus, Dosidicus gigas and Moroteuthis robusta.
Gonatus fabricii is found in the North Atlantic and North Pacific at
high latitudes and it seems likely that these populations are connected
at least periodically via Arctic seas. The genus Todarodes has an
Atlantic species, T . sagittatus, and a North Pacific species T. paci$cua
MALCOLM R. CLARKE
The breeding season must extend over a long period because
larvae of less than 0.5 cm in length are present off West Africa from
March to October. Size distributions for the various months suggest
that most of the spawning takes place in winter. In October the squids
are half grown and they are thought to mature and breed the following
winter and then perhaps die (Bruun, 1943). However, this cannot be
regarded as settled because the division of the size distribution into
size groups can only be described as arbitrary.
A specimen was taken from the mouth of a deep-sea fish (Dall).
XXI. DISTRIBUTION
As pointed out in the introduction, our knowledge of the group is
probably not good enough to draw general conclusions concerning the
relationships between the cephalopod fauna of different geographical
areas. However, it is perhaps useful to list the species recorded from
general areas (Table 111, Fig. 55). Boundaries of these have been
rather arbitrarily chosen and are useful for descriptive purposes rather
than for marking any real faunistic barriers; in most cases their
position has been determined by geographical expediency. To some
extent the total number of species and the number of “endemic”
species in any area is related to the amount of work done in that area
(cf. Table I11 and Fig. 1).
The distribution of a few of the better known species is worth
noting as they are oegopsid representatives of previously recognized
types. Hyaloteuthis pelagicus, Onychoteuthis banksi, Ommustrephes
bartrami, Onychia carribaea, Thysanoteuthis rhombus, Brachioteuthis
riisei, Lycoteuthis diadema, Cranchia scabra and the sepioid Spirula
spirula are widespread in warm and temperate waters. Bathyteuthis
abyssicola, Abraliopsis morissi and Histioteuthis bonellii are found
in the Atlantic and Indian Ocean. Symplectoteuthis oualaniensis (both
forms) and Abralia andamanica are found in the Indian Ocean and the
Pacific. Better known species which are restricted to particular oceans
are in the North Atlantic Illex illecebrosus, in the North Atlantic and
the Mediterranean Ommastrephes caroli, Illex coindeti and Abralia
veranyi, in the North and South Atlantic and Mediterranean Ommastrephes pteropus, Todarodes sagittatus and Todaropsis eblanae, in the
Indian Ocean Brachioteuthis picta and in the Pacific Symplectoteuthis
luminosa, Todarodes paci$cus, Dosidicus gigas and Moroteuthis robusta.
Gonatus fabricii is found in the North Atlantic and North Pacific at
high latitudes and it seems likely that these populations are connected
at least periodically via Arctic seas. The genus Todarodes has an
Atlantic species, T . sagittatus, and a North Pacific species T. paci$cua